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3 years ago

Help please thank you so much ❤️

Chemistry

1 answer:

mart [117]3 years ago

6 0

Answer:

a)0.326

because pb's atomic mass is 207

mol = mass ÷ atomic mass

mol = 67.5 ÷ 207

mol = 0.326...

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Carbon tetrachloride can be produced by the following reaction: Suppose 1.20 mol of and 3.60 mol of were placed in a 1.00-L flas

hjlf

The given question is incomplete. The complete question is :

Carbon tetrachloride can be produced by the following reaction:

$CS_2(g)+3Cl_2(g)\rightleftharpoons S_2Cl_2(g)+CCl_4(g)$

Suppose 1.20 mol $CS_2(g)$ of and 3.60 mol of $Cl_2(g)$ were placed in a 1.00-L flask at an unknown temperature. After equilibrium has been achieved, the mixture contains 0.72 mol of $CCl_4$ . Calculate equilibrium constant at the unknown temperature.

Answer: The equilibrium constant at unknown temperature is 0.36

Explanation:

Moles of $CS_2$ = 1.20 mole

Moles of $Cl_2$ = 3.60 mole

Volume of solution = 1.00 L

Initial concentration of $CS_2$ = $\frac{moles}{volume}=\frac{1.20mol}{1L}=1.20M$

Initial concentration of $Cl_2$ = $\frac{moles}{volume}=\frac{3.60mol}{1L}=3.60M$

The given balanced equilibrium reaction is,

$CS_2(g)+3Cl_2(g)\rightleftharpoons S_2Cl_2(g)+CCl_4(g)$

Initial conc. 1.20 M 3.60 M 0 0

At eqm. conc. (1.20-x) M (3.60-3x) M (x) M (x) M

The expression for equilibrium constant for this reaction will be,

$K_c=\frac{[S_2Cl_2]\times [CCl_4]}{[Cl_2]^3[CS_2]}$

Now put all the given values in this expression, we get :

$K_c=\frac{(x)\times (x)}{(3.60-3x)^3\times (1.20-x)}$

Given :Equilibrium concentration of $CCl_4$ , x = $\frac{moles}{volume}=\frac{0.72mol}{1L}=0.72M$

$K_c=\frac{(0.72)\times (0.72)}{(3.60-3\times 0.72)^3\times (1.20-0.72)}$

$K_c=0.36$

Thus equilibrium constant at unknown temperature is 0.36

4 0

2 years ago

Roman55 [17]

Answer:

305 litres of NO gas will be produced from 916 L of NO₂

Explanation:

Given the balanced equation of the chemical reaction as follows:

3 NO₂ (g) + H₂O( l) —— 2 HNO₃ (l) + NO (g)

Under standard conditions, 3 moles of No₂ will react with 1 mole of water to produce 1 mole of NO gas.

Molar volume of a gas at STP is 22.4 L

Number of moles of NO₂ gas present in 916 L = 916/22.4 = 40.893 moles of NO₂ gas

From the mole ratio of NO₂ to NO in the equation of reaction,

Number of moles of NO that will be produced = 1/3 × 40.893 moles = 13.631 moles of NO gas

Volume of 13.631 moles of NO gas = 13.631 × 22.4

Volume of NO gas produced = 305.334L

Therefore, Volume of NO gas produced from the reaction of 916 L of NO₂ with water = 305 L

5 0

2 years ago

Identify three factors that characterize aquatic systems

givi [52]

While terrestrial biomes are shaped by air temperature and precipitation, aquatic systems are characterized by factors such as water salinity, depth, and whether the water is moving or standing. If that's what you mean?

3 0

2 years ago

The gas in a sealed container has an absolute pressure of 125.4 kilopascals. If the air around the container is at a pressure of

AlexFokin [52]

Answer: C. 25.6 kPa

Explanation:

The Gauge pressure is defined as the amount of pressure in a fluid that exceeds the amount of pressure in the atmosphere.

As such, the formula will be,

PG = PT – PA

Where,

PG is Gauge Pressure

PT is Absolute Pressure

PA is Atmospheric Pressure

Inputted in the formula,

PG = 125.4 - 99.8

PG = 25.6 kPa

The gauge pressure inside the container is 25.6kPa which is option C.

4 0

3 years ago

During the combustion of a peanut that weighed 0.341 g, the temperature of the 100 mL of water in the calorimeter rose from 23.4

blondinia [14]

Answer:

119 kCal per serving.

Explanation:

The heat energy necessary to elevates water's temperature from 23.4°C to 37.9°C can be calculated by the equation below:

Q = mcΔT

Q: heat energy

m: mass in g

c: specific heat capacity in cal/g°C

ΔT = temperature variation in °C

m is the mass of water, considering the density of water to be 1g/mL, 100 mL of water weights 100g. Therefore:

Q = 100 g x 1.00 cal/g°C x (37.9 - 23.4)°C

Q = 1450 cal

1450 cal ____ 0.341 g peanuts

x ____ 28 g peanuts

x = 119061.58 cal

This means that the cal from fat per serving of peanuts is at least 119 kCal.

3 0

3 years ago