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3 years ago

what is the concentration of 10.00ml of HBr if it takes 16.73 mL of a 0.253M LiOH solution to neutralize it?

1 answer:

4 0

The chemical reaction would be expressed as follows:

HBr + LiOH = LiBr + H2O

We are given the volumes and corresponding concentration to be used for the reaction. We use these values to solve for the concentration of the other reactant. We do as follows:

0.253 mol LiOH / L solution ( 0.01673 L ) ( 1 mol HBr / 1 mol LiOH ) = 0.00423 HBr needed

Concentration of HBr =0.00423mol / .010 L = <span>0.423 M HBr </span>

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If 43.1 g of O2 and 6.8 g of CO2 are placed in a 13.7 L container at 34 degrees C, what is the mixture of gasses?

jonny [76]

Answer:

The total pressure of the gas mixture = 2.76 atm

Note: The question is not complete. The complete question is as follow:

If 43.1 g of O2 and 6.8 g of CO2 are placed in a 13.7 L container at 34 degree Celsius , what is the pressure of the mixture of gases?

Explanation:

Mass of O₂ gas = 43.1 g, molar mass of O₂ gas = 32.0 g/mol

Number of moles of O₂ gas = 43.1/32.0 = 1.347 moles

Mass of CO₂ gas = 6.8 g, molar mass of CO₂ gas = 44.0 g

Number of moles of CO₂ gas = 6.8/44 = 0.155 moles

Total number of moles of gas mixture, n = (1.347 + 0.155) = 1.502 moles

Volume of gas mixture, V = 13.7 L

Temperature of gas mixture, T = 34 °C = (273.15 + 34) K = 307.15 K

Pressure of gas mixture = ?

Molar gas constant, R = 0.0821 liter·atm/mol·K.

Using the ideal gas equation: PV =nRT

P = nRT/V

P = (1.502 × 0.0821 × 307.15) / 13.7

P = 2.76 atm

Therefore, the total pressure of the gas mixture = 2.76 atm

5 0

3 years ago

Read the chemical equation.

Sladkaya [172]

Answer:- D. 1.8 moles of Fe and $2.7molCO_2$ .

Solution:- The balanced equation is:

$Fe_2O_3+3CO\rightarrow 2Fe+3CO_2$

let's first figure out the limiting reactant using the given moles and mol ratio:

$1.8molFe_2O_3(\frac{3molCO}{1molFe_2O_3})$

= 5.4 mol CO

From calculations, 5.4 moles of CO are required to react completely with 1.8 moles of Iron(III)oxide but only 2.7 moles of CO are available. It means CO is limiting reactant.

Products moles depends on limiting reactant. Let's calculate the moles of each reactant formed for given 2.7 moles of CO.

$2.7molCO(\frac{2molFe}{3molCO})$

= 1.8 mol Fe

$2.7molCO(\frac{3molCO_2}{3molCO})$

= $2.7molCO_2$

So, the correct choice is D. 1.8 moles of Fe and $2.7molCO_2$ are formed.

6 0

3 years ago

Hydrazine, n2h4, is used as a rocket fuel. in the reaction below, if 80.1 g of n2h4 and 92.0 g of n2o4 are allowed to react, how

Mama L [17]

Answer is: excess of hydrazine is 16 grams.
Chemical reaction: N₂O₄(l) + 2N₂H₄(l) → 3N₂(g) + 4H₂<span>O(g).
</span>m(N₂H₄) = 80,1 g.
m(N₂O₄) = 92,0 g.
n(N₂H₄) = m(N₂H₄) ÷ M(N₂H₄).
n(N₂H₄) = 80,1 g ÷ 32 g/mol.
n(N₂H₄) = 2,5 mol.
n(N₂O₄) = 92 g ÷ 92 g/mol.
n(N₂O₄) = 1 mol; limiting reactant.
From chemical reaction: n(N₂H₄) : n(N₂O₄) = 2 : 1.
n(N₂H₄) = 2 mol reacts.
Δn(N₂H₄) = 2,5 mol - 2 mol = 0,5 mol.
Δm(N₂H₄) = 0,5 mol · 32 g/mol = 16 g.

6 0

3 years ago

820 g Li2SO4 is dissolved into 2500 mL of solution. What is the molar concentration?

Andreas93 [3]

Molarity is defined as the moles of solute per liter of solution. $M=\frac{n}{V}$ . Where M is molarity, n is the number of moles and V is the volume. First we must find the molar mass of $Li_2SO_4$ which is 109.98 g/mol

$Li_2SO_4= 2 \times Li_{Ar} + S_{Ar} + 4 \times O_{Ar}\\= (2 \times 6.941 + 32.1 + 4 \times 16.0) = 109.98 g/mol$

$820\ g\ Li_2SO_4 \times \frac{mol}{109.98\ g}= 7.46\ mol\ Li_2SO4$

Then we find the molarity using above equation

$M= \frac{n}{V} = \frac{7.46 mol}{2500ml} \times\frac{1000ml}{L} = 2.98\ M$

6 0

3 years ago

Based on the kinetic molecular theory, which of the following statements is correct about a sample of gas at a constant temperat

Scilla [17]

Answer:

C) It has a constant average kinetic energy

Explanation:

The average kinetic energy of the particles in a gas is directly proportional to the temperature of the gas, according to the equation.

k is the Boltzmann's constant

T is the absolute temperature of the gas

Therefore, temperature of a gas is a measure of the average kinetic energy of the particles.

In this problem, we are told that the gas is at constant temperature (and volume): therefore, according to the previous equation, this means that the average kinetic energy is also constant.

8 0

3 years ago