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4 years ago

Given an element’s atomic number and mass number, how can you tell the number of protons and neutrons in its nucleus?

Chemistry

2 answers:

hram777 [196]4 years ago

8 0

Are there any choices or is that the only part of the question?

Charra [1.4K]4 years ago

4 0

Explanation:

Atomic number is the number of protons present in an atom. Whereas mass number is the sum of total number of protons and neutrons present in an atom.

For example, atomic number of bromine is 35, that is, there are 35 protons present in a bromine atom. The mass number of bromine is 80.

So, Mass number = no. of protons + no. of neutrons

no. of neutrons = mass number - no. of protons

= 80 - 35

= 45

Hence, in a bromine atom there are 35 protons and 45 neutrons.

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Try It: Evidence of Population Change

erma4kov [3.2K]

The answer to this would be false.

4 0

3 years ago

The first step in industrial nitric acid production is the catalyzed oxidation of ammonia. Without a catalyst, a different react

murzikaleks [220]

Answer: The value of $K_{eq}$ is $4.84\times 10^{-5}$

Explanation:

We are given:

Initial moles of ammonia = 0.0280 moles

Initial moles of oxygen gas = 0.0120 moles

Volume of the container = 1.00 L

Concentration of a substance is calculated by:

$\text{Concentration}=\frac{\text{Number of moles}}{\text{Volume}}$

So, concentration of ammonia = $\frac{0.0280}{1.00}=0.0280M$

Concentration of oxygen gas = $\frac{0.0120}{1.00}=0.0120M$

The given chemical equation follows:

$4NH_3(g)+3O_2(g)\rightleftharpoons 2N_2(g)+6H_2O(g)$

Initial: 0.0280 0.0120

At eqllm: 0.0280-4x 0.0120-3x 2x 6x

We are given:

Equilibrium concentration of nitrogen gas = $3.00\times 10^{-3}M=0.003$

Evaluating the value of 'x', we get:

$\Rightarrow 2x=0.003\\\\\Rightarrow x=0.0015M$

Now, equilibrium concentration of ammonia = $0.0280-4x=[0.0280-(4\times 0.0015)]=0.022M$

Equilibrium concentration of oxygen gas = $0.0120-3x=[0.0120-(3\times 0.0015)]=0.0075M$

Equilibrium concentration of water = $6x=(6\times 0.0015)]=0.009M$

The expression of $K_{eq}$ for the above reaction follows:

$K_{eq}=\frac{[H_2O]^6\times [N_2]^2}{[NH_3]^4\times [O_2]^3}$

Putting values in above expression, we get:

$K_{eq}=\frac{(0.009)^6\times (0.003)^2}{(0.022)^4\times (0.0075)^3}\\\\K_{eq}=4.84\times 10^{-5}$

Hence, the value of $K_{eq}$ is $4.84\times 10^{-5}$

4 0

3 years ago

2. What are the factors that influence the two types of energy?

VikaD [51]

Answer:

It depends on the objects mass, the gravitational pull when up or down slopes, and the height of the reference point

3 0

3 years ago

Which law states that at constant temperature the pressure of a given amount of gas is inversely proportional to the volume of t

Phantasy [73]

That law is known as Boyle's Law, "The volume of a given mass of a gas is inversely related to pressure when the temperature is constant"

8 0

4 years ago

Explain why smell is a physical property?

lawyer [7]

Answer:

because no chemical change is happening

Explanation:

5 0

3 years ago