Testimonial evidence is:
a. a statement made under oath by a competent witness
b. verbal statements made by the prosecutor to establish a fact
c. used to determine the significance of class evidence
d. the same as indirect evidence

C2H2 will be left  when the burning is complete.

The equation of the reaction is; 2C2H2 + 5O2 --> 4CO2 + 2H2O

The number of moles of C2H2 reacting is = 1.20 g/26 g/mol = 0.046 moles

The number of moles of O2 is = 3.50 g/32 g/mol = 0.109 moles

Since;

2 mole of C2H2 reacts with 5 moles of O2

x moles of C2H2 reacts with 0.109 moles of O2

x = 2 mole × 0.109 moles/5 moles

x = 0.044 moles of C2H2.

It then follows that C2H2 is the reactant in excess so C2H2  will be left  when the burning is complete.

Learn more: https://brainly.com/question/9743981?

The half-life for the transmutation of radon-222 to lead-214 is 3.8 days. If there is an initial mass of 100.0 g of radon-222, we can calculate how much radon-222 would remain after 7.6 days.

After one half-life (3.8 days), half of the radon-222 would decay. So, we are left with 50.0 g of radon-222. Now, after another 3.8 days (a total of 7.6 days), another half of the remaining radon-222 would decay. Therefore, we would have half of 50.0 g remaining, which is 25.0 g of radon-222 after 7.6 days.

The decay process follows an exponential decay model, where the remaining amount decreases by half with each half-life. By understanding the concept of half-life, we can determine the amount of radon-222 that would remain after a given time period. In this case, with an initial mass of 100.0 g and a half-life of 3.8 days, we calculate that 25.0 g of radon-222 would be left after 7.6 days.

To know more about Radioactive isotope :

brainly.com/question/28039996

#SPJ11

Answer:

165.3 cm^3

Explanation: hope this is correct!!

P1 * V1 / T1 = P2 * V2 / T2

P1 = 84.6 kPa

V1 = 215 cm³

T1 = 23.5°C = 23.5 + 273 K = 296.5 K

At STP:

P2 = 101.3 kPa

V2 = ?

T2 = 273 K

Answer:

\( \huge{ \boxed{1.993 \times {10}^{11} \: moles}}\)

Explanation:

To find the number of moles in a substance given it's number of entities we use the formula;

\( n = \dfrac{N}{L} \\ \)

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

From the question

N = 1.20 × 10³⁵ formula units

\(n = \dfrac{1.2 \times {10}^{35} }{6.02 \times {10}^{23} } = \\ 1.993 \times {10}^{11} \: moles\)

We have the final answer as

Answer:

the answer is A ( The basement)

HOPE THAT HELPSSS!!!

Answer the basement

Explanation: i took the test

In the Diels-Alder lab procedure, a wet paper towel serves a crucial purpose in maintaining the desired temperature for the reaction. The Diels-Alder reaction is a cycloaddition process that involves the formation of a new six-membered ring through the reaction between a diene and a dienophile. Temperature control is important for this reaction to proceed efficiently and achieve the desired product.

The wet paper towel is typically wrapped around the reaction vessel, such as a test tube or a flask, to provide a cooling effect. This is necessary because the Diels-Alder reaction is exothermic, meaning it releases heat during the reaction process. If the temperature becomes too high, it may lead to side reactions or decomposition of the reactants, lowering the yield and purity of the final product.

By using a wet paper towel, you create a simple, cost-effective method of temperature control. As the water in the paper towel evaporates, it absorbs heat from the surrounding environment, including the reaction vessel. This process, known as evaporative cooling, helps maintain a stable temperature within the reaction mixture, allowing the Diels-Alder reaction to proceed effectively and produce the desired product.

Learn more about wet paper towel here:

https://brainly.com/question/31587351

#SPJ11

To calculate the percent hydrolysis in a 0.075 M sodium acetate (NaCH3COO) solution, we first need to understand the concept of hydrolysis. Hydrolysis is the process in which a substance reacts with water to produce new compounds. In the case of sodium acetate, it can hydrolyze to form acetic acid (CH3COOH) and sodium hydroxide (NaOH).

For this calculation, we need to use the formula for percent hydrolysis:
Percent Hydrolysis = ([H+] × 100) / [CH3COO-]
First, we need to find the concentration of H+ ions in the solution. We can use the ion product of water (Kw) and the dissociation constant of acetic acid (Ka) to do this   Kw = [H+][OH-]
Ka = [H+][CH3COO-] / [CH3COOH]
Since sodium acetate is the conjugate base of acetic acid, we can use the Ka of acetic acid to find the Kb of sodium acetate:  Kb = Kw / Ka
Now, we can write an expression for the equilibrium concentration of hydrolyzed sodium acetate:
Kb = [OH-][CH3COOH] / [CH3COO-]
Since [OH-] = [CH3COOH] (stoichiometrically), we can simplify the equation as: Kb = [OH-]^2 / [CH3COO-]
We can now solve for [OH-], and subsequently for [H+] using the Kw equation. Finally, plug the calculated [H+] and initial concentration of sodium acetate (0.075 M) into the percent hydrolysis formula to find the answer: Percent Hydrolysis = ([H+] × 100) / [CH3COO-]
Based on the given options, the closest calculated value will be the correct percent hydrolysis.

To know more about hydrolysis

https://brainly.com/question/4352413

#SPJ11

The correct option is D. 2) Anti-bonding electrons or lone pairs. These lone pairs, and bonds helps to form the shape which keeps these electrons separate as possible.

Answer:

4

Explanation:

bc Ca is 1 C is one L is two

a. When the temperature is decreased, the reaction will shift to the right in order to produce more heat and counteract the decrease in temperature.
b. When the volume is decreased, the reaction will shift to the left in order to decrease the pressure.
4. To calculate the pH of a 0.25 M solution of propylamine (C3H7NH2),

we need to use the equation:
Kb = [C3H7NH3+][OH-]/[C3H7NH2]
6.9*10-4 = (x)(x)/(0.25)
x = 0.0132 M
pOH = -log[OH-] = -log(0.0132) = 1.88
pH = 14 - pOH = 14 - 1.88 = 12.12
Therefore, the pH of the solution is 12.12.
5. To calculate the pH of a 0.20 M solution of Ba(CN)2, we need to use the equation:
Ka = [HCN][OH-]/[CN-]
4.4*10-5 = (x)(x)/(0.20)
x = 0.0021 M
pH = -log[H+] = -log(0.0021) = 2.68
Therefore, the pH of the solution is 2.68.

To know more about pH refer here:

https://brainly.com/question/15289741

#SPJ11

Answer:

A- Upwelling

Explanation:

If we triple the temperature and double the volume, The new pressure of the system be 10atm.

The equation of state for a fictitious ideal gas is known as the ideal gas law. Although it has several drawbacks, it is a decent approximation of the behaviour of numerous gases under various circumstances. The formula for the ideal gas equation is

To find pressure we us ideal gas equation:

PV = nRT

Therefore, if we multiply Volume by 2 and Temperature by 3, we get.

hence, by adding.

Given that nR are constant throughout, P (2V)=nR(3T).

then would only consider variables

P = 3T/2V

So p = 1.5 T/V

It can alternatively be expressed as P/1.5=T/V.

Pressure would therefore drop by a factor of 1.5 division.

The new pressure of the system is 10atm.

learn more about ideal gas law Refer:brainly.com/question/12624936

#SPJ4

The data provided is a set of values for two variables: fertilizer concentration (mg/L) and mean plant height (cm). In this case, the appropriate type of graph to represent the relationship between these variables would be a line graph.

A line graph is commonly used to display the relationship between two continuous variables, where one variable is plotted on the x-axis and the other variable on the y-axis. In this scenario, the fertilizer concentration (mg/L) would be plotted on the x-axis, while the mean plant height (cm) would be plotted on the y-axis.

A line graph is suitable in this case because it helps visualize the trend or pattern in the data over a continuous range of values. It shows the continuous relationship between the fertilizer concentration and the corresponding mean plant height. By connecting the data points with a line, it allows for an understanding of the overall trend or relationship between the two variables.

A bar graph, on the other hand, is more appropriate for categorical or discrete data where the x-axis represents distinct categories or groups, rather than a continuous range. Since the fertilizer concentrations in this case are represented by specific values (0 mg/L, 0.70 mg/L, 1.3 mg/L, 1.7 mg/L), a bar graph would not effectively represent the continuous relationship between the variables.

Therefore, to accurately represent the relationship between the fertilizer concentration and mean plant height in this scenario, a line graph should be used.


To know more about graph , click here,https://brainly.com/question/17267403


#SPJ11

Based on the data provided,  the rate of the given reactions are:

a. reaction rate =  0.0132 M/sec

b. rate of change of [H⁺] = 8.8 * 10⁻³ M/sec

Reaction rate = change in concentration of reactant or product/ time taken

Change in concentration of I⁻ = 1.000 M - 0.868 M= 0.132

time taken = 10 s

reaction rate = 0.132/10

Rate of reaction = 0.0132 M/sec

From the equation of the reaction 3 moles of I⁻ are used up for every 2 moles of H⁺

Hence, the rate of change of [H⁺] = 0.0132 M/sec * 2/3

rate of change of [H⁺] = 8.8 * 10⁻³ M/sec

Therefore, the rate of the given reactions are:

a. reaction rate =  0.0132 M/sec

b. rate of change of [H⁺] = 8.8 * 10⁻³ M/sec

Learn more about reaction rate at: https://brainly.com/question/24795637

Answer:

To calculate the volume of oxygen required to burn hydrogen, we need to use the balanced chemical equation for the combustion of hydrogen with oxygen which is

2H2(g) + O2(g) → 2H2O(g)

Two moles of hydrogen gas combine with one mole of oxygen gas to form two moles of water vapour, according to this equation. The coefficients in the equation provide information on the mole ratios of the reactants and products.

To determine the volume of oxygen necessary, we must first convert the problem's circumstances to standard temperature and pressure (STP), which are 0 degrees Celsius and 101.3 kPa. This conversion may be accomplished using the ideal gas law:

PV = nRT

where P is the pressure, V is the volume, n is the number of moles, R is the gas constant, and T is the temperature in Kelvin.

Next step is to convert the temperature of -50 degrees Celsius to Kelvin:

T = (−50 + 273.15) K = 223.15 K

Now we can use the ideal gas law to calculate the number of moles of hydrogen required for the reaction:

n(H2) = PV/RT = (50 kPa)(V)/(8.314 J/(mol·K))(223.15 K)

where we have used the units of the gas constant R in Joules per mole Kelvin (J/(mol·K)).

The stoichiometry of the balanced chemical equation may then be used to calculate the amount of moles of oxygen required for the reaction. Because the hydrogen-to-oxygen ratio is 2:1, we require half as many moles of oxygen as hydrogen:

n(O2) = n(H2)/2

Finally, we can use the ideal gas law again to calculate the volume of oxygen required at STP:

n(O2) = PV/RT = (101.3 kPa)(V)/(8.314 J/(mol·K))(273.15 K)

Now we can substitute the expression for n(O2) in terms of n(H2) into the equation for V(O2) and solve for V(O2):

V(O2) = n(O2)RT/P = [(50 kPa)(V)/(8.314 J/(mol·K))(223.15 K)](8.314 J/(mol·K))(273.15 K)/(101.3 kPa)

Simplifying this expression and solving for V(O2), we get:

V(O2) = (V/2) * (101.3/50) * (273.15/223.15) = 3.07 V

As a result, at -50 degrees Celsius and 50 kPa, the volume of oxygen required to burn a given volume of hydrogen in space is 3.07 times the volume of hydrogen. It should be noted that the volume units will be determined by the initial volume supplied for hydrogen in the problem.

(im so sorry if its wrong)

The dissociation constant (Kd) of the ligand is approximately 0.6667.

To determine the dissociation constant (Kd) of a ligand, we need information about the equilibrium concentrations of the bound and unbound forms of the ligand.

Given:

Percent occupancy = 60% = 0.60

[Ligand] = 10^(-7) M

The percent occupancy represents the fraction of ligand that is bound to the receptor, while (1 - percent occupancy) represents the fraction of ligand that is unbound. Therefore, we can write:

Bound ligand concentration = Percent occupancy × [Ligand]

Unbound ligand concentration = (1 - Percent occupancy) × [Ligand]

Substituting the given values:

Bound ligand concentration = 0.60 × 10^(-7) M

Unbound ligand concentration = (1 - 0.60) × 10^(-7) M

Now, we can define the dissociation constant (Kd) as the ratio of the concentrations of unbound and bound ligands:

Kd = [Unbound ligand] / [Bound ligand]

Kd = [(1 - 0.60) × 10^(-7) M] / [0.60 × 10^(-7) M]

Kd = (0.40 × 10^(-7) M) / (0.60 × 10^(-7) M)

Kd ≈ 0.6667

Therefore, the dissociation constant (Kd) of the ligand is approximately 0.6667.

Learn more about dissociation constant here:

https://brainly.com/question/28197409

#SPJ11

The number of reactants is less than the number of products in a decomposition reaction.

This is the type of chemical reaction which involves a reactant being broken down into two or more products.

This means the number of product is always greater than the reactant which is why option C was chosen.

Read more about Decomposition reaction here https://brainly.com/question/1465225

#SPJ1

a. NH3 (Ammonia): In a 1.0L container of NH3 at Standard Temperature and Pressure (STP), intermolecular forces such as hydrogen bonding would be exerted.

b) 1.0L container of CHCl3 at STP, dipole-dipole interactions (along with London dispersion forces) would be present.

a. NH3 (Ammonia):

In a 1.0L container of NH3 at Standard Temperature and Pressure (STP), intermolecular forces such as hydrogen bonding would be exerted. Ammonia (NH3) molecules consist of one nitrogen atom bonded to three hydrogen atoms, forming a trigonal pyramidal shape.

Hydrogen bonding is a type of intermolecular force that occurs when a hydrogen atom is covalently bonded to an electronegative atom (in this case, nitrogen) and interacts with another electronegative atom (in this case, the nitrogen atom of a neighboring NH3 molecule).

b. CHCl3 (Chloroform):

In a 1.0L container of CHCl3 (chloroform) at STP, intermolecular forces such as dipole-dipole interactions would be exerted. Chloroform (CHCl3) molecules consist of one carbon atom bonded to three hydrogen atoms and one chlorine atom, forming a tetrahedral shape.

Dipole-dipole interactions arise due to the difference in electronegativity between chlorine and hydrogen atoms. The chlorine atom is more electronegative than hydrogen, resulting in a polar covalent bond.

While dipole-dipole interactions are present in CHCl3, it is worth noting that CHCl3 also exhibits London dispersion forces. These forces occur due to temporary fluctuations in electron distribution, creating temporary dipoles.

London dispersion forces are the weakest type of intermolecular force but still contribute to the overall intermolecular interactions in CHCl3.

For more such questions on Standard Temperature and Pressure visit:

https://brainly.com/question/14820864

#SPJ8

Answer: Water is SUPER soluble and regarded as an universal solvent because it is polar in nature and dissolves most inorganic solutes and some polar organic solutes to form aqueous solutions.

Explanation:

WATER is a substance which is composed of the elements such as hydrogen and oxygen that are combined in the ratio of 2:1. The physical properties of water include:

--> it is a colourless, odourless and tasteless liquid and

--> the boiling point of water is 100°C(this is due to the presence of hydrogen bonding).

The solubility of a solute in a solvent at a particular temperature is the maximum amount of solute in moles or grams that will saturate 1000 dm³ or grams of the solvent.

Water is regarded as a universal solvent BECAUSE it is capable of dissolving many substances. This solubility helps maintain different processes in life such as acting as the solvent which helps cells transport and use substances like oxygen or nutrients.

A pure substance has definite composition and constant properties in all of the sample

Characteristics and Properties Of Pure Substances

Thus we can conclude that  a pure substance has definite composition in all of the sample

Learn more about pure substances at https://brainly.com/question/18634105

#SPJ9

The organic product formed when 1−hexyne is treated with H₂O, H₂SO₄, and HgSO₄ will be 2-hexanone (structure attached).

This reaction is an example of an oxymercuration reaction of the organic product 1−hexyne.

Oxymercuration is shown in three steps to the right. The nucleophilic double bond attacks the mercury ion, releasing an acetoxy group. The mercury ion's electron pair attacks carbon on the double bond, generating a positive-charged mercuronium ion. Mercury's dxz and 6s orbitals give electrons to the double bond's lowest unoccupied molecular orbitals.

In the second stage, the nucleophilic H₂O attacks the highly modified carbon, freeing its mercury-bonding electrons. Electrons neutralize mercury ions by collapsing. Water molecules have positive-charged oxygen.

In the third stage, the negatively charged acetoxy ion released in the first step attacks the hydrogen of the water group, generating the waste product HOAc. The two electrons in the oxygen-hydrogen link collapse into oxygen, neutralizing its charge and forming alcohol.

You can also learn about organic products from the following question:

https://brainly.com/question/13513481

#SPJ4

Explanation:

6. Which type mixture does not allow light to shine through?

D) Suspensions

10. What is a closed system in chemical equilibrium?

Solution:

-TheUnknownScientist

According to the question the molarity of the Ba(OH)2 solution is then 0.976 M.

What is molarity?

Molarity is a unit of measurement for concentration of a solute in a solution. It is defined as the number of moles of the solute per liter of solution. Molarity is often used to describe the concentration of ions, molecules, or other constituents in a solution. It is an important parameter in many areas of chemistry, including analytical, organic, and inorganic chemistry.

The molarity of a solution can be calculated using the expression M =  moles of solute/liters of solution. In this case, the moles of solute is the amount of Ba(OH)2 in the solution, which can be calculated using the amount of HNO3 required to titrate it.

Since 1 mole of HNO3 reacts with 1 mole of Ba(OH)2, the moles of Ba(OH)2 can be calculated using the amount of HNO3 used in the titration. The equation is moles of Ba(OH)2 = (20.4 mL)(1.13 M)(1 L/1000 mL) = 0.02292 moles. The molarity of the Ba(OH)2 solution is then M = 0.02292 moles/23.43 mL = 0.976 M.

To learn more about molarity

https://brainly.com/question/26873446

#SPJ1

When transferring a drum of flammable solvent into a storage tank, certain bonding and grounding procedures must be are as follows:-

The following are the bonding and grounding procedures that should be followed:

Step 1: BondingBefore starting the transfer process, the drum and the tank should be bonded together. Bonding refers to the creation of a conductive path between two objects to equalize their static electric charges. The bonding cable should be connected to both the drum and the tank to ensure that they are at the same potential and eliminate any chance of electrostatic discharge.

Step 2: Grounding - Grounding refers to the connection of the objects to reliable earth ground. The tank should be grounded to the earth's ground to discharge any static electricity that may have built up on the tank's surface. The grounding cable should be connected to the tank's grounding lug, which is located on the tank's exterior surface.

Step 3: Check for continuity before starting the transfer process, check that the bonding and grounding connections are secure and that there is continuity in the bonding and grounding paths. A continuity check can be performed using a multimeter. If the readings are abnormal, rectify the situation before proceeding with the transfer process.

Step 4: Monitor the transfer process during the transfer process, it is essential to monitor the bonding and grounding connections continuously. If there is any break in continuity, stop the transfer immediately and rectify the situation before proceeding. Also, use a static-resistant container and a grounded funnel to minimize the risk of electrostatic discharge.

To know more about static electric charges please refer:

https://brainly.com/question/2916022

#SPJ11

Explanation:

What type of floor. You have uploaded no image

We can you gauge the efficiency of the reaction carried out in the laboratory is by the percent yield.

The efficiency of the chemical reaction cab be the measured  by the percent yield of the reaction with  the value of the theoretical value. The theoretical value is the value that is estimated the amount of the product formed by the chemical reaction. The actual yield is the the laboratory concentration that is obtained from the chemical reaction. So, the percent yield is used to determine the efficiency.

Thus, The percent yield is the measurement  of the efficiency of the reaction that is carried out in the laboratory.

To learn more about efficiency here

https://brainly.com/question/14408642

#SPJ4