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seraphim [82]
3 years ago
6

What does the number 7 mean in the following example-73Li?

Chemistry
1 answer:
Pavlova-9 [17]3 years ago
4 0

Answer:

7 is the mass number of li and 3 is the atomic number

a 3

b 7

c 3

d 4

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Calculate the number of grams of Hydrogen required to produce 5.73 grams of water. 2H2+O2--->2H2O 2 grams 0.636 grams 1.2 gra
rusak2 [61]

Explanation:

32

2H

2

+O

2

→2H

2

O

Molecular mass of H

2

=2 g/mol

Molecular mass of O

2

=32 g/mol

From the balanced chemical equation,

2×2=4 g of hydrogen requires 32 g of Oxygen to react completely

3 0
3 years ago
A reaction of importance in the formation of smog is that between ozone and nitrogen monoxide described by O 3 ( g ) + NO ( g )
Aleksandr [31]

Answer:

(a) 7.11x10⁻⁴ M/s

(b) 2.56 mol.L⁻¹.h⁻¹

Explanation:

(a) The reaction is:

O₃(g) + NO(g) → O₂(g) + NO₂(g)   (1)

The reaction rate of equation (1) is given by:

rate = k*[O_{3}][NO]     (2)

<u>We have:</u>

k: is the rate constant of reaction = 3.91x10⁶ M⁻¹.s⁻¹

[O₃]₀ = 2.35x10⁻⁶ M

[NO]₀ = 7.74x10⁻⁵ M

Hence, to find the inital reacion rate we will use equation (2):

rate = k*[O_{3}]_{0}[NO]_{0} = 3.91 \cdot 10^{6} M^{-1}s^{-1}*2.35\cdot 10^{-6} M*7.74 \cdot 10^{-5} M = 7.11 \cdot 10^{-4} M/s  

Therefore, the inital reaction rate is 7.11x10⁻⁴ M/s

(b) The number of moles of NO₂(g) produced per hour per liter of air is:

t = 1 h

V = 1 L

\frac{\Delta[NO_{2}]}{\Delta t} = rate

\frac{\Delta[NO_{2}]}{\Delta t} = 7.11 \cdot 10^{-4} M/s*\frac{3600 s}{1 h} = 2.56 mol.L^{-1}.h{-1}

Hence, the number of moles of NO₂(g) produced per hour per liter of air is 2.56 mol.L⁻¹.h⁻¹

I hope it helps you!                                

5 0
3 years ago
Determine the mass of hydrogen contained in 9.06 x 1024 H2O molecules.
Elza [17]

Answer:

15.2 g H2

Explanation:

2H2O -> 2H2 + O2

9.06 x 10^24 molecules x (1 mol/6.022 x 10^23 molecules) x (2 mol H2/2 mol H2O) x (1.008 g/1 mol) = 15.2 g H2

4 0
3 years ago
In the Haber reaction, patented by German chemist Fritz Haber in 1908, dinitrogen gas combines with dihydrogen gas to produce ga
VashaNatasha [74]

The question is incomplete, complete question is :

In the Haber reaction, patented by German chemist Fritz Haber in 1908, dinitrogen gas combines with dihydrogen gas to produce gaseous ammonia. This reaction is now the first step taken to make most of the world's fertilizer. Suppose a chemical engineer studying a new catalyst for the Haber reaction finds that 348 liters per second of dinitrogen are consumed when the reaction is run at 205°C and 0.72 atm. Calculate the rate at which ammonia is being produced.

Answer:

The rate of production of ammonia is 217.08 grams per second.

Explanation:

N_2+3H_2\rightarrow 2NH_3

Volume of dinitrogen used in a second = 348 L

Temperature of the gas = T = 205°C = 205+273 K = 478 K

Pressure of the gas = P = 0.72 atm

Moles of dinitrogen = n

n=\frac{PV}{RT}=\frac{0.72 atm\times 348 L}{0.0821 atm L/mol K\times 478 K}=6.385 mol

According to reaction, 1 mole of dinitriogen gives 2 mole of ammonia.Then 6.385 moles of dinitrogen will give:

\frac{2}{1}\times 6.385 mol=12.769 mol

Mass of 12.769 moles of ammonia;

12.769 mol 17 g/mol = 217.08 g

217.08 grams of ammonia is produced per second.So, the rate of production of ammonia is 217.08 grams per second.

6 0
4 years ago
Li + HNO3 &gt; LiNO3 + H2 how do I balance it? Show work pls
azamat

Answer: The balanced equation is 2Li + 2HNO_{3} \rightarrow 2LiNO_{3} + H_{2}.

Explanation:

The given reaction equation is as follows.

Li + HNO_{3} \rightarrow LiNO_{3} + H_{2}

Number of atoms present on reactant side are as follows.

  • Li = 1
  • H = 1
  • NO_{3} = 1

Number of atoms present on product side are as follows.

  • Li = 1
  • H = 2
  • NO_{3} = 1

To balance this equation, multiply Li by 2 and HNO_{3} by 2 on reactant side. Also, multiply LiNO_{3} by 2 on product side.

Hence, the equation can be rewritten as follows.

2Li + 2HNO_{3} \rightarrow 2LiNO_{3} + H_{2}

Now, number of atoms present on reactant side are as follows.

  • Li = 2
  • H = 2
  • NO_{3} = 2

Number of atoms present on product side are as follows.

  • Li = 2
  • H = 2
  • NO_{3} = 2

As there are same number of atoms on both reactant and product side. Hence, the equation is now balanced.

Thus, we can conclude that the balanced equation is 2Li + 2HNO_{3} \rightarrow 2LiNO_{3} + H_{2}.

3 0
3 years ago
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