Answer:
The amount of Co2 generated is 15 moles
Explanation:
It bears the same ratio with Carbon meaning oxygen was used in excess
What is the average atomic mass of 10 hydrogen -1 molecules?
Answer:
1.674 x 10^-23 grams
Explanation:
Hydrogen-1 is called Protium
wikipedia
atomic mass of Protium is 1.00794 amu
sciencedirectcom
atomic mass of 10 Protiums is 10.0794 amu
10.0794 amu in grams is
1.6737236x10^-23 grams
What is the frequency of gamma radiation with energy of 6.96 x 10-14 J?
The frequency of gamma radiation is calculated to be = 1.11 *10^20 Hz.
What is gamma radiation?A gamma radiation is also known as gamma ray. It is a penetrating form of electromagnetic radiation arising from radioactive decay of atomic nuclei. It consists of shortest wavelength electromagnetic waves, even shorter than X-rays.
Gamma rays can pass through the human body completely and as they pass through, they cause ionizations that damage tissue and DNA.
As we know that E= hf
Hence, f= E/h
Given E= 6.96 x 10-14 J
And, Planck's constant, h = 6.626 *10^-34 m² kg/s
f = 6.96 * 10^-14J +/6.626 *10^-34
f = 1.11 *10^20 Hz
Hence, frequency of gamma radiation = 1.11 *10^20 Hz.
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I can't copy and paste it because brainly responds with "Don't use such phrases here, not cool! It hurts our feelings =("
The true statements are;
The reaction is endothermic
Heat is a reactant
ΔHrxn is 89 kJ/mol
What is the enthalpy?Enthalpy is a thermodynamic property that represents the total energy of a system, including both its internal energy (the energy of its constituent particles) and the energy it has due to its temperature and pressure. It is commonly used in energy analysis and heat transfer calculations and is expressed in units of joules (J) or calories (cal).
We know that the enthalpy of the reaction can obtained from;
Enthalpy of the products - Enthalpy of the reactants
ΔH reaction = 2(-391.4) - 2(-435.9)
(-782.8) - (-871.8)
= 89 kJ/mol
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Will y’all find this answer real quick for me !!
The mass (in grams) of sodium carbonate, Na₂CO₃ required to produce 85 grams of barium carbonate, BaCO₃ is 45.7 grams
How do i determine the mass of sodium carbonate, Na₂CO₃ required?First, we shall observe the balanced equation to obtain useful information. This is shown below:
Na₂CO₃ + BaSO₄ -> BaCO₃ + Na₂SO₄
Molar mass of BaCO₃ = 197 g/molMass of BaCO₃ from the balanced equation = 1 × 197 = 197 g Molar mass of Na₂CO₃ = 106 g/molMass of Na₂CO₃ from the balanced equation = 1 × 106 = 106 gFrom the balanced equation above,
197 g of BaCO₃ were obtained from 106 g of Na₂CO₃
With the above information, we can obtain the mass of sodium carbonate, Na₂CO₃ required to produce 85 grams of barium carbonate, BaCO₃. This is illustrated below:
From the balanced equation above,
197 g of BaCO₃ were obtained from 106 g of Na₂CO₃
Therefore,
85 g of BaCO₃ will be obtain from = (85 × 106) / 197 = 45.7 g of Na₂CO₃
Thus, we can conclude from the above calculation that the mass of sodium carbonate, Na₂CO₃ required is 45.7 grams
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Determine the volume (in mL) of 1.00 M NaOH that must be added to 250 mL of 0.50 M CH3CO₂H to produce a buffer with a pH of 4.50.
Approximately 70.57 mL of 1.00 M NaOH should be added to 250 mL of 0.50 M CH3CO₂H to produce a buffer with a pH of 4.50.
To determine the volume of 1.00 M NaOH required to produce a buffer with a pH of 4.50 when added to 250 mL of 0.50 M CH3CO₂H, we need to consider the Henderson-Hasselbalch equation and the stoichiometry of the reaction.
The Henderson-Hasselbalch equation for a buffer solution is given as:
pH = pKa + log([A-]/[HA])
In this case, CH3CO₂H (acetic acid) acts as the weak acid (HA) and CH3COO- (acetate ion) acts as its conjugate base (A-). We are given that the desired pH is 4.50, and we can determine the pKa value for acetic acid from reference sources, which is approximately 4.75.
Using the Henderson-Hasselbalch equation, we can rearrange it to solve for the ratio [A-]/[HA]:
[A-]/[HA] = 10^(pH - pKa)
[A-]/[HA] = 10^(4.50 - 4.75) = 10^(-0.25) = 0.5623
This means that the ratio of the acetate ion to acetic acid in the buffer solution should be approximately 0.5623.
To calculate the required volume of NaOH, we need to consider the stoichiometry of the reaction. Acetic acid reacts with hydroxide ions (OH-) to form acetate ions and water:
CH3CO₂H + OH- → CH3COO- + H2O
The stoichiometric ratio between acetic acid and hydroxide ions is 1:1. Therefore, the volume of 1.00 M NaOH needed can be calculated using the equation:
Volume (NaOH) × 1.00 M = Volume (CH3CO₂H) × 0.50 M × 0.5623
Volume (NaOH) = (Volume (CH3CO₂H) × 0.50 M × 0.5623) / 1.00 M
Volume (NaOH) = (250 mL × 0.50 M × 0.5623) / 1.00 M
Volume (NaOH) ≈ 70.57 mL
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Diamond and graphite are two crystalline forms of carbon. At 1 atm and 25°C, diamond changes to graphite so slowly that the enthalpy change of the process must be obtained indirectly. Determine ΔHrxn for
C(diamond) → C(graphite)
with equations from the following list:
(1) C(diamond) + O2(g) → CO2(g) ΔH = −395.4 kJ
(2) 2 CO2(g) → 2 CO(g) + O2(g) ΔH = 566.0 kJ
(3) C(graphite) + O2(g) → CO2(g) ΔH = −393.5 kJ
(4) 2 CO(g) → C(graphite) + CO2(g) ΔH = −172.5 kJ
The enthalpy change of the reaction C(diamond) → C(graphite) is -2.9 kJ.
The given information is ΔHrxn for the reaction C(diamond) → C(graphite) can be calculated with the given equations:Equations: C(diamond) + O2(g) → CO2(g) ΔH = −395.4 kJ 2 CO2(g) → 2 CO(g) + O2(g) ΔH = 566.0 kJ C(graphite) + O2(g) → CO2(g) ΔH = −393.5 kJ 2 CO(g) → C(graphite) + CO2(g) ΔH = −172.5 kJThe required reaction can be obtained by adding the equations (1) and (4), as follows:C(diamond) + O2(g) + 2CO(g) → C(graphite) + 3CO2(g)Addition of the two equations (1) and (4) results in a reaction whose products are C(graphite) and CO2.
To get the final equation that involves only the required reactants and products, the equation (2) should be added, which consumes CO2 and produces O2, as shown below:C(diamond) + O2(g) → CO2(g) ΔH = −395.4 kJ [eq. (1)] 2 CO(g) → C(graphite) + CO2(g) ΔH = −172.5 kJ [eq. (4)] 2 CO2(g) → 2 CO(g) + O2(g) ΔH = 566.0 kJ [eq. (2)] C(diamond) + O2(g) + 2CO(g) → C(graphite) + 3CO2(g) ΔHrxn=ΣΔHf(products)−ΣΔHf(reactants) ΔHrxn=[(3 mol CO2)(-393.5 kJ/mol) + (1 mol C(graphite))(0 kJ/mol)] − [(1 mol C(diamond))(0 kJ/mol) + (1 mol O2)(0 kJ/mol) + (2 mol CO(g))(−172.5 kJ/mol)] − [(2 mol CO2)(566.0 kJ/mol)] ΔHrxn=−2.9 kJ.
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5
How many J of energy are needed to raise the temperature of 18.3 g of
water from 11.88°C to 49.32°C?*
2540 J
1740 J
2870 J
3570 J
Q = mcΔT, where Q is the heat energy, m is the mass, c is the specific heat, and ΔT is the change in temperature (T₂-T₁). The specific heat of water is 4.184 J/g °C. We are given the mass of water (m = 18.3 g), the final temperature (T₂ = 49.32 °C), and the initial temperature (T₁ = 11.88 °C). The change in temperature, ΔT, equals 49.32 °C - 11.88 °C = 37.44 °C. With all these values at hand, we can solve for the amount of energy needed, Q:
Q = (18.3 g)(4.184 J/g °C)(37.44 °C) = 2866.7 J ≈ 2870 J (three sig figs).
If you produced 5 moles of Ca3(PO4)2, how many moles of NaCl did you also produce?
15 moles of NaCl would have been used up in the reaction as a result.
What volume of Ca3 PO4 2 will be generated?The number of moles is obtained by taking each mass and dividing it by the molar mass. The molar mass of Ca₃(PO₄)₂ is 310.18 grammes/mole. The result is 0.016 moles of Ca₃(PO₄)₂ when five is divided by 310.18.
The balanced chemical equation for the reaction of sodium chloride (NaCl) and calcium phosphate (Ca₃(PO₄)₂) is:
3Ca₃(PO₄)₂ + 6NaCl → 6NaPO₄ + CaCl₂ + 2Ca₃(PO₄)₂
calculate the amount of NaCl consumed using the following proportion:
2 mol Ca₃(PO₄)₂ / 6 mol Sodium Chloride = 5 mol Ca₃(PO₄)₂ / x
Solving for x, we get:
x = (6 mol NaCl × 5 mol Ca₃(PO₄)₂) / 2 mol Ca₃(PO₄)₂
x = 15 mol NaCl
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Tiana is a chemist who is making a
chemical to add to swimming pools in order
to make the water safer. She mixed two solid
substances together in a sealed container.
The diagram above shows the repeating
groups of atoms that make up the two
starting substances.
After mixing, Tiana found two liquid
substances in the sealed container.
(Nothing had escaped.) Which of the
diagrams to the left shows the repeating
groups of atoms that make up the ending
substances?
Answer: A
Explanation:
grams of hydrogen contains the same number of atoms as 9.79 grams of nitrogen?
Answer:
1.44 g
Explanation:
1. get number of nitrogen atoms in 9.79 grams of nitrogen
1 mole of Nitrogen is 6.022 x 10^23 atoms N which is = 14.01g N
2.
if 6.022 x 10^23 atoms of Nitrogen is 14
then x atoms of Nitrogen is 9.79
3.
6.022 x 10^23/ x = 14/9.79 ->
x = 8.431 x 10^24 / 9.79 =
8.61799714478 x 10^23
4.
8.61799714478 x 10^23 atoms of N
6.022 x 1023 atoms of H have a mass of 1.008g, so
8.61799714478 x 10^23 atoms of H have a mass of (1.008/6.022 x 1023) x 8.61799714478 x 10^23) = 1.44250051072175g
1.44 g
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When traveling through a different medium, light waves _________.
refract
reflect
speed up
stop moving
Answer: Refract
Explanation:
A student borrows $10,000 from a bank but ends up paying $13,000 on the
loan over the next five years. How much interest did the student pay?
The student paid an interest of $3,000 over the next five years.
HOW TO CALCULATE INTEREST:
The interest on a borrowed amount of money can be calculated by subtracting the principal from the amount paid over time. That is;
Interest = principal - amount
According to this question, a student borrows $10,000 from a bank but ends up paying $13,000. This means that the principal is $10,000 while the amount is $13,000. The interest is calculated thus;
Interest = $13,000 - $10,000
Interest = $3,000
Therefore, the student paid an interest of $3,000 over the next five years.
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Which reactions performed in the experiment
involved chemical changes?
crushing calcium carbonate
mixing calcium carbonate and HCI
boiling water
heating copper (II) sulfate pentahydrate
separating iron filing and sulfur
mixing potassium iodide and lead nitrate
combining magnesium and HCI
burning the candle
DONE
Mixing calcium carbonate and HCl
Heating copper sulfate pentahydrate
Mixing potassium iodide and lead nitrate
Combining magnesium and HCl
Burning the candle.
The crushing of limestone is a bodily trade it no longer alters the chemical composition of the limestone. The heating of limestone is a chemical trade the limestone decomposes into two other materials, lime and carbon dioxide. both ended in gas formation. both ended in shade change.
Rust is not anything however Iron Oxide is a brand new substance shaped out of the response. The color of the floor of the iron additionally modifications. hence, rusting of iron is a chemical trade. Rusting is an instance of chemical exchange. A chemical property describes the ability of a substance to go through a particular chemical alternate. The chemical belonging of iron is that it is miles capable of combining with oxygen to form iron oxide, the chemical call of rust. like several steel carbonates, calcium carbonate reacts with acidic solutions to supply carbon dioxide gas.
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Consider how sodium chloride and butane interact with water: ______is more Iikely to dissolve In water because it is_____and is attracted to the______of water:
Sodium chloride is more likely to dissolve in water because it is polar and is attracted to the polar molecules of water. On the other hand, butane is nonpolar and is not attracted to the polar molecules of water, so it is less likely to dissolve.
Sodium chloride, also known as table salt, has ionic bonds, meaning it is composed of positive and negative ions. The positive sodium ion and negative chloride ion are attracted to the polar water molecules, which have a positive charge at one end and a negative charge at the other. This attraction between the ions of salt and the polar water molecules leads to the dissolution of salt in water.
Butane, on the other hand, is a nonpolar substance. It is composed of nonpolar carbon and hydrogen atoms arranged in a linear structure. These nonpolar atoms are not attracted to the polar water molecules, so they do not dissolve well in water. In fact, butane is a hydrocarbon and is one of the components of natural gas. It is a fuel that is used for heating and cooking, and it is not soluble in water.
In conclusion, the solubility of a substance in water depends on its molecular structure and the type of bonds it contains. Polar substances tend to dissolve well in water because they are attracted to the polar water molecules, while nonpolar substances are less likely to dissolve because they are not attracted to the polar water molecules.
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In an industrial process ethanol C2H60 burns with O2 to produce heat. Each mole of ethanol produces 8842 joules during the reaction.
C2H5OH (1) + 3 O2(g) 2 CO2(g) + 3 H2O(0) + 8842 Joules
How many Kilojoules are obtained from burning 982.6 g of ethanol?
Answer:
\(189kJ\)
Explanation:
Hello!
In this case, since one mole of ethanol release 8,842 J per 1 mole of ethanol, we can write:
\(\frac{8,842J}{1molC_2H_6H}\)
Thus, since we need the energy released by 982.6 g of ethanol, we compute the moles in such mass of fuel:
\(n=982.6g\frac{1mol}{46.08g} =21.3mol\)
Therefore, the result is:
\(\frac{8,842J}{1mol}*21.3mol=188,545J\)
Which in kJ is:
\(189kJ\)
Best regards!
Is hydrogen found in a natural abundance
Yes, hydrogen found in a natural abundance, hydrogen is easily the most abundant element in the universe.
Why is hydrogen the most abundant in nature?Hydrogen the most abundant in nature because hydrogen is the simplest element in the universe, with only one proton and one electron ,it is the only element without a neutron.
The element hydrogen is by far the most abundant in the universe. It can be found in the sun and most stars, and the planet Jupiter is mostly made up of hydrogen. Water is the most abundant form of hydrogen on Earth.
Thus, hydrogen found in a natural abundance.
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A liquid ester used to flavour food is believed to be impure. What would be the best way of testing its purity?
Answer:
Filter it
Explanation:
Atomic number: 19 is what Chemical symbol?
Answer:
oficialismo hemostasia Jalisco
Answer:
K
Explanation:
Potassium is atomic no 19 and it is k because is from kalium, the Meldiaeval Latin for potash, which may have derived from an arabic word quality, meaning alkali.
Atomic mass, 39.098amu
Oxidation status, +1
Year discovered, 1807
Melting point, 63.28 degrees Celsius(145.90degrees Fahrenheit )
Boiling point, 760 degrees Celsius (1400 degrees Fahrenheit )
CHEM FINAL TOMORROW!!! I'm struggling with a few concepts, if anyone could help explain this to me & how to do it, I'd be very grateful!!!
Based on the given reaction, the acid-base pairs in this reaction are:
HCO₃⁻ (acid) and NH₃ (base)NH₄⁺ (acid) and CO₃²⁻ (base)What are the acid-base pairs in the given reaction?An acid-base pair refers to a set of two chemical species that are related through the transfer of a proton (H+ ion) during a chemical reaction.
One species acts as an acid by donating a proton, while the other acts as a base by accepting that proton.
In the given reaction:
HCO₃⁻ (aq) + NH₃ (aq) → NH₄⁺ + CO₃²⁻
An acid-base pair can be identified as follows:
HCO₃⁻ (bicarbonate ion) can act as an acid by donating a proton (H⁺), becoming CO₃⁻.
NH₃ (ammonia) can act as a base by accepting a proton (H⁺), becoming NH₄⁺ (ammonium ion).
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Identify the substance that has formula mass of 133.5amu.
(a) MgCI
b)SCI
c)BCI
D) AICI
The calculated formula masses to 133.5 amu, we find that the substance with a formula mass closest to 133.5 amu is (d) AlCl3. Therefore, the answer is option D.
To identify the substance with a formula mass of 133.5 amu, we need to calculate the formula mass of each given substance and compare it to 133.5 amu.
(a) MgCl2:
The formula mass of MgCl2 can be calculated by adding the atomic masses of magnesium (Mg) and chlorine (Cl).
Mg: atomic mass = 24.31 amu
Cl: atomic mass = 35.45 amu
Formula mass of MgCl2 = (24.31 amu) + 2(35.45 amu) = 95.21 amu
(b) SCl:
The formula mass of SCl can be calculated by adding the atomic masses of sulfur (S) and chlorine (Cl).
S: atomic mass = 32.07 amu
Cl: atomic mass = 35.45 amu
Formula mass of SCl = 32.07 amu + 35.45 amu = 67.52 amu
(c) BCl:
The formula mass of BCl can be calculated by adding the atomic mass of boron (B) and chlorine (Cl).
B: atomic mass = 10.81 amu
Cl: atomic mass = 35.45 amu
Formula mass of BCl = 10.81 amu + 35.45 amu = 46.26 amu
(d) AlCl3:
The formula mass of AlCl3 can be calculated by adding the atomic mass of aluminum (Al) and 3 times the atomic mass of chlorine (Cl).
Al: atomic mass = 26.98 amu
Cl: atomic mass = 35.45 amu
Formula mass of AlCl3 = 26.98 amu + 3(35.45 amu) = 133.78 amu. Option D
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The first-order rate constant for the decomposition of N2O5
2N2O5(g)→4NO2(g)+O2(g)
at 70∘C is 6.82×10−3 s−1. Suppose we start with 2.70×10−2 mol of N2O5(g)
in a volume of 2.5 L
1) How many moles of N2O5 will remain after 7.0 min?
2)How many minutes will it take for the quantity of N2O5 to drop to 1.7×10−2 mol?
3)What is the half-life of N2O5 at 70 ∘C?
15. Triglycerides, waxes, and steroids are all ___ lipids because they contain only carbon, hydrogen, and oxygen
A. simple
B. methyl esters
C. complex
D. long-chain compounds
Answer:
A. simple
Explanation:
type of reaction based on the reactants
FeCl3 +K →
Answer:
complexation
Explanation:
KSCN + FeCl 3 → K + + [FeSCN] 2+ + 3 Cl. This is a complexation reaction: [FeSCN] 2+ is the formed complex.
I need help with this question
Answer:
I think It's the 2nd "There are two compounds present"
The total number of atoms does not change in a chemical reaction. This is commonly
known as the Law of Conservation of ____ ?
1.Atoms
2.Matter
3.Physics
Pls help i have 0 clue what this even means
Show all work including units and the equation you used to solve. Carbon dioxide gas has a molar mass of 44 g/mol. At 300K and 1.5atm, a sample of carbon dioxide has a volume of 4.5 L. Find the number of moles of the carbon dioxide.
EXTRA POINTS: Find the mass of the carbon dioxide.
Answer: 0.27 moles of CO2 and 11.88 grams of CO2
Explanation: Use the Ideal Gas Law, PV = nRT, substitute the values given and solve.
I can't seem to upload procedure but:
P = 1.5atm
V = 4.5L
n = moles
R = 0.0821gr/mol (when using atm, kPa is 8.31)
T = 300K
Isolate what you don't have, in this case n. Change PV = nRT to PV/RT = n. Substitute the values to get moles. Once you have this, multiply the value by the molar mass of CO2 (44gr/mol) to get the mass of CO2 in grams.
You have 85.63 g of CO2, how many molecules of CO2 are in that
container?
Ans:
______X 1024 molecules of CO2
Explanation:
1.17×10^24 molecules of co2
4. What is the necessary volume of H₂ in order to obtain 5.0 g of propane (C3H8)? Assume that dH2=0,09g/l
The necessary volume of H₂ gas to obtain 5.0 g of propane (C₃H₈) is approximately 12.60 liters.
To determine the necessary volume of H₂ gas to obtain 5.0 g of propane (C₃H₈), we need to use the molar ratio between H₂ and C₃H₈, as well as the density of H₂ gas.
First, let's calculate the molar mass of propane (C₃H₈):
C: 12.01 g/mol
H: 1.01 g/mol
Molar mass of C₃H₈ = (3 * C) + (8 * H) = (3 * 12.01) + (8 * 1.01) = 44.11 g/mol
Next, we can determine the number of moles of propane (C₃H₈) using its mass:
Number of moles = Mass / Molar mass
Number of moles of C₃H₈ = 5.0 g / 44.11 g/mol ≈ 0.1134 mol
Now, we can establish the molar ratio between H₂ and C₃H₈ from the balanced chemical equation:
C₃H₈ + 5H₂ → 3CH₄
According to the balanced equation, 5 moles of H₂ are required to produce 1 mole of C₃H₈.
Therefore, the number of moles of H₂ required can be calculated as:
Number of moles of H₂ = 5 * Number of moles of C₃H₈ = 5 * 0.1134 mol = 0.567 mol
Finally, we can determine the necessary volume of H₂ gas using the ideal gas law equation:
Volume = (Number of moles * Gas constant * Temperature) / Pressure
Given that the density of H₂ is 0.09 g/L, we can convert it to moles per liter:
Density = Mass / Volume
0.09 g/L = 2 g/mol / Volume (since the molar mass of H₂ is 2 g/mol)
Solving for Volume:
Volume = 2 g/mol / 0.09 g/L ≈ 22.22 L/mol
Now, we can calculate the necessary volume of H₂ gas:
Volume of H₂ = Number of moles of H₂ * Volume per mole
Volume of H₂ = 0.567 mol * 22.22 L/mol ≈ 12.60 L
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How does meiosis cause siblings to have similar physical characteristics, while not being identical to each other?
Meiosis cause siblings to have similar physical characteristics, while not being identical to each other because meiosis creates new combinations of genetics material in each of the four daughter cell
During meiosis homologous chromosomes pair along their length and the chromosomes cross over at point called chiasma at each chiasma the chromosomes break and rejoin and trading some of their genes and this recombination result in genetics variation
meiosis creates new combination of genetic material in each of the four doughtier cell and this new combination result from the exchange of DNA between paired chromosome and such exchange means that the gametes produced through meiosis exhibit an amazing range of genetic variation
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Can anyone help me understand how to calculate the moles of H+ and OH-?
To calculate the moles of H+ and OH-, you need to know the concentration of the solution in terms of its pH or pOH value.
How to calculate the molesWhen you get the pH of the solution, you can use this formula to calculate the concentration of H+ ions: [H+] = 10^(-pH)
Also, if you know the pOH of the solution, you can use this formula to calculate the concentration of OH- ions: [OH-] = 10^(-pOH)
Having determined the concentration of H+ and OH- ions, the molarity formula can be used to calculate the number of moles of each ion as follows: moles = concentration (in mol/L) x volume (in L)
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