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Consider the chemical reaction: 2 cu(no3)2â†’ 2 cuo (s) + 4 no2 (g) + o2 (g)when 9.378 g of cu(no3)2 completely decomposed, how

Allushta [10]

2Cu(NO3)2 ----------> 2CuO (s) +4NO2 (g) + O2(g)

9.378g=0.05moles

no of moles = weight / MW = 9.378/187.56 = 0.05moles

as per the above reaaction 2moles of Cu(NO3)2 can produce 4moles of N2

0.05moles Cu(NO3)2 can produce (0.05*4)/2 = 0.1moles of N2

and 2moles of Cu(NO3)2 can produce 1moles of O2

0.05moles Cu(NO3)2 can produce (0.05*1)/2 = 0.025moles of O2

Total moles of gas i.e., N2 and O2 =0.1+0.025 = 0.125moles

From PV = nRT

V = nRT/ P = 0.125*0.0821*273 = 2.80166Lit option is correct

6 0

3 years ago

Small quantites of hydrogen gas can be prepared in the laboratory by the addition of aqueous hydrochloric acid to metallic zinc.

ira [324]

Answer: The mass or zinc reacted is 0.624 grams.

Explanation:

We are given:

Total pressure = 1.032 atm

Vapor pressure of water = 32 torr = 0.042 atm (Conversion factor: 1 atm = 760 torr)

To calculate partial pressure of hydrogen gas, we use the equation:

$p_{H_2}=p_T-p_{H_2O}\\\\p_{H_2}=1.032-0.042=0.99atm$

To calculate the number of moles of hydrogen gas, we use the equation given by ideal gas follows:

$PV=nRT$

where,

P = pressure of hydrogen gas = 0.99 atm

V = Volume of hydrogen gas = 240. mL = 0.240 L (Conversion factor: 1 L = 1000 mL)

T = Temperature of hydrogen gas = $30^oC=[30+273]K=303K$

R = Gas constant = $0.0821\text{ L. atm }mol^{-1}K^{-1}$

n = number of moles of hydrogen gas = ?

Putting values in above equation, we get:

$0.99atm\times 0.240L=n\times 0.0821\text{ L atm }mol^{-1}K^{-1}\times 303K\\n=\frac{0.99\times 0.240}{0.0821\times 303}=9.55\times 10^{-3}mol$

The chemical equation for the reaction of zinc and hydrochloric acid follows:

$Zn+2HCl\rightarrow ZnCl_2+H_2$

By Stoichiometry of the reaction:

1 mole of hydrogen gas is produced from 1 mole of zinc metal

So, $9.55\times 10^{-3}mol$ of hydrogen gas is produced from = $\frac{1}{1}\times 9.55\times 10^{-3}=9.55\times 10^{-3}mol$ of zinc metal

To calculate the mass of zinc metal, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Molar mass of zinc = 65.38 g/mol

Moles of zinc = $9.55\times 10^{-3}$ moles

Putting values in above equation, we get:

$9.55\times 10^{-3}mol=\frac{\text{Mass of zinc}}{65.38g/mol}\\\\\text{Mass of zinc}=(9.55\times 10^{-3}mol\times 65.38g/mol)=0.624g$

Hence, the mass or zinc reacted is 0.624 grams.

4 0

3 years ago

Draw a mechanism for the reaction of methylamine with 2-methylpropanoic acid. Draw any necessary curved arrows. Show the product

Nitella [24]

Answer:

See figure 1

Explanation:

On this case we have a base (methylamine) and an acid (2-methyl propanoic acid). When we have an acid and a base an acid-base reaction will take place, on this specific case we will produce an ammonium carboxylate salt.

Now the question is: ¿These compounds can react by a nucleophile acyl substitution reaction? in other words ¿These compounds can produce an amide? 

Due to the nature of the compounds (base and acid), the nucleophile (methylamine) doesn't have the ability to attack the carbon of the carbonyl group due to his basicity. The methylamine will react with the acid-producing a positive charge on the nitrogen and with this charge, the methylamine loses all his nucleophilicity.

I hope it helps!

5 0

3 years ago

The electrical wires in your home use what type of circuits?

Helga [31]

The house wiring should be done parallel because, in parallel connection there will be more advantages than a series connection.

Let a house is wired in series and it contains a fan, tube light, TV, refrigerator. All the devices are connected in series. Now, due to some disturbance the fan speed working or it burned. Then since the connection was a series, due to one appliance failure causes the whole circuit to fail. If it is burned that means it making an open circiut. Then there will be no current flow in the circuit.

Now if it was a parallel connection as we know already, the parallel connection is nothing but individual appliances connected to the same line by tappings. That means there's no dependency of one appliance on another. So if an appliance fail or burns it doesn't effects the remaining appliances. And there will be uninterrupted supply to the healthy appliances can be achieved.

That’s why we use parallel for house wiring

7 0

3 years ago

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How does the smell of food being cooked spread so fast ???

sladkih [1.3K]

Answer:

When we cook food in the kitchen, that's the region of higher concentration of the smell. By diffusion, the smell spreads to the whole room and thereby whole house, so anyone standing at a distance, can smell it.

5 0

3 years ago

Read 2 more answers