All categories

3 years ago

3. Mr. Hill has 27 students in his class

Chemistry

2 answers:

stich3 [128]3 years ago

4 0

Just dived both numbers by two

Vlad [161]3 years ago

4 0

Answer: the answer for mr hills class is 13 and the answer for mr chang is 12

Explanation: The thing that i did was just divide the numbers by 2 and the number is how many teams can be formed at once in both classes

You might be interested in

. Citric acid, which can be obtained from lemon juice, has the molecular formula C6H8O7. A 0.250-g sample of citric acid dissolv

marysya [2.9K]

Answer:

3 acidic hydrogens per molecule of citric acid

Explanation:

In a sample of 37.2 mL(0.0372 L) of 0.105 mol/L of NaOH, will have:

n = 0.105x0.0372 = 0.0039 mol of NaOH

The dissociation of NaOH will give the same number of moles of Na⁺ and OH⁻.

The molar mass of citric acid is:

C: 12g/mol x 6 = 72 g/mol

H: 1g/mol x 8 = 8g/mol

O: 16 g/mol x 7 = 112 g/mol

192 g/mol

So, 0.250g of the acid has

n = mass/molar mass

n = 0.250/192

n = 0.0013 mol.

To be neutralized, it will be necessary 0.0039 mol of acidic hydrogens to react with the 0.0039 mol of OH⁻.

The dissociation reaction of one molecule of the acid will give the stoichiometry:

1 mol of acid ----------------------- x mol of acidic hydrogens

0.0013 mol --------------------------- 0.0039

For a simple direct three rule:

0.0013x = 0.0039

x = 3 acidic hydrogens per molecule of citric acid.

3 0

4 years ago

Please help out thanks

ra1l [238]

Answer:

Granite

Explanation:

The specific heat capacity of a substance, which is denoted by "c", is the amount of heat required to raise the temperature of a particular mass of that substance by 1°C. It is calculated as follows:

c = Q ÷ m∆T

Where;

c = specific heat capacity

Q = amount of heat (J)

m = mass of substance

∆T = change in temperature.

According to this equation and explanation above, a low specific heat capacity means that the rate at which the temperature is raised is slow and vice versa. Hence, from this question, GRANITE with specific capacity of 0.790 J/gK will raise temperature the slowest.

3 0

3 years ago

The Haber process for the production of ammonia is the main industrial process of producing ammonia today. Prior to developing t

Schach [20]

Answer:

Equilibrium constant for the reaction at 25⁰C = 1.81 x 10⁻⁶

Explanation:

Reaction for the Haber's process

N₂(g) + 3 H₂(g) ⇌ 2 NH₃(g)

Free energy change of reaction

ΔGr° = ∑products free energy - ∑reactants free energy

= 2 x (- 16.4) - 0

= - 32.8 KJ / mole

Equilibrium constant for this reaction at 25⁰C

ΔGr° = - 2.303 RT log K

⇒ log K = $\frac{-32.8}{2.303 X8.314X10^{-3}X 298 }$

⇒ K = Anti log( -5.74) = 1.81 x 10⁻⁶

6 0

4 years ago

In a report to a supervisor, a chemist described an experiment in the following way: "0.0800 mol of H2O2 decomposed into 0.0800

lapo4ka [179]

Answer:

H2O2 → H2O + 1/2O2

Explanation:

0.0800 mol of H2O2 decomposed into 0.0800 mol of H2O and 0.0400 mol of O2

H2O2 → H2O + 1/2O2 - Descomposition reaction.

7 0

4 years ago

You had a closed tank of air at a pressure of 4 atm and temperature of 20 degrees Celsius. When the tank and the air are heated

notka56 [123]

Answer:

The pressure will be 4.27 atm.

Explanation:

Gay-Lussac's law can be expressed mathematically as follows:

$\frac{P}{T} =k$

Where P = pressure, T = temperature, K = Constant

This law indicates that the quotient between pressure and temperature is constant.

This law indicates that, as long as the volume of the container containing the gas is constant, as the temperature increases, the gas molecules move faster. Then the number of collisions with the walls increases, that is, the pressure increases. That is, the pressure of the gas is directly proportional to its temperature.

In short, when there is a constant volume, as the temperature increases, the pressure of the gas increases. And when the temperature is decreased, the pressure of the gas decreases.

You want to study two different states, an initial state and a final state. You have a gas that is at a pressure P1 and a temperature T1 at the beginning of the experiment. By varying the temperature to a new value T2, then the pressure will change to P2, and the following will be fulfilled:

$\frac{P1}{T1} =\frac{P2}{T2}$

In this case:

P1= 4 atm
T1= 20 C= 293 K (being 0 C= 273 K)
P2= ?
T2= 40 C= 313 K

Replacing:

$\frac{4 atm}{293 K} =\frac{P2}{313 K}$

Solving:

$P2= 313 K* \frac{4 atm}{293 K}$

P2= 4.27 atm

<u><em>The pressure will be 4.27 atm.</em></u>

8 0

3 years ago