All categories

3 years ago

What does an atomic number represent in an atom?

Chemistry

2 answers:

egoroff_w [7]3 years ago

6 0

Answer: An atomic number represent protons in an atom.

Explanation:

An atom consists of electrons, protons, and neutrons. The protons and neutrons are present inside the nucleus of an atom whereas the electrons revolve around the nucleus of an atom.

The number of protons in an atom represents the atomic number of that particular atom. Further, this atomic number determines the place of each atom in the periodic table and its chemical properties.

For example, the mass number of sodium atom is 23 that is number of protons and neutrons. The atomic number of sodium is 11 that means there are 11 protons. The number of neutrons will be 23 - 11 = 12.

seraphim [82]3 years ago

5 0

It represents the number of protons in the nucleus of an atom which determines the chemical properties of an element.

You might be interested in

Calculate the number of moles and the mass of the solute in each of the following solutions:

frosja888 [35]

Answer:

For a: The number of moles of KI are $2.7\times 10^{-5}$ and mass is $4.482\times 10^{-3}g$

For b: The number of moles of sulfuric acid are $1.65\times 10^{-5}$ and mass is $1.617\times 10^{-3}g$

For c: The number of moles of potassium chromate are $2.84\times 10^{-2}$ and mass is 5.51 g.

For d: The number of moles of ammonium sulfate are 39.018 moles and mass is 5155.84 grams.

Explanation:

To calculate the molarity of solution, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Moles of solute}}{\text{Volume of solution (in L)}}$ .....(1)

To calculate the number of moles of a substance, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(2)

For a:

Molarity of KI = $8.23\times 10^{-5}M$

Volume of solution = 325 mL = 0.325 L (Conversion factor: 1 L = 1000 mL)

Putting values in equation 1, we get:

$8.25\times 10^{-5}mol/L=\frac{\text{Moles of KI}}{0.325L}\\\\\text{Moles of KI}=2.7\times 10^{-5}mol$

Now, using equation 2, we get:

Moles of KI = $2.7\times 10^{-5}mol$

Molar mass of KI = 166 g/mol

Putting values in equation 2, we get:

$2.7\times 10^{-5}mol=\frac{\text{Mass of KI}}{166g/mol}\\\\\text{Mass of KI}=4.482\times 10^{-3}g$

Hence, the number of moles of KI are $2.7\times 10^{-5}$ and mass is $4.482\times 10^{-3}g$

For b:

Molarity of sulfuric acid = $22\times 10^{-5}M$

Volume of solution = 75 mL = 0.075 L

Putting values in equation 1, we get:

$22\times 10^{-5}mol/L=\frac{\text{Moles of sulfuric acid}}{0.075L}\\\\\text{Moles of }H_2SO_4=1.65\times 10^{-5}mol$

Now, using equation 2, we get:

Moles of sulfuric acid = $1.65\times 10^{-5}mol$

Molar mass of sulfuric acid = 98 g/mol

Putting values in equation 2, we get:

$1.65\times 10^{-5}mol=\frac{\text{Mass of }H_2SO_4}{98g/mol}\\\\\text{Mass of }H_2SO_4=1.617\times 10^{-3}g$

Hence, the number of moles of sulfuric acid are $1.65\times 10^{-5}$ and mass is $1.617\times 10^{-3}g$

For c:

Molarity of potassium chromate = $0.1135M$

Volume of solution = 0.250 L

Putting values in equation 1, we get:

$0.1135mol/L=\frac{\text{Moles of }K_2CrO_4}{0.250L}\\\\\text{Moles of }K_2CrO_4=2.84\times 10^{-2}mol$

Now, using equation 2, we get:

Moles of potassium chromate = $2.84\times 10^{-2}mol$

Molar mass of potassium chromate = 194.2 g/mol

Putting values in equation 2, we get:

$2.84\times 10^{-2}mol=\frac{\text{Mass of }K_2CrO_4}{194.2g/mol}\\\\\text{Mass of }K_2CrO_4=5.51g$

Hence, the number of moles of potassium chromate are $2.84\times 10^{-2}$ and mass is 5.51 g.

For d:

Molarity of ammonium sulfate = 3.716 M

Volume of solution = 10.5 L

Putting values in equation 1, we get:

$3.716mol/L=\frac{\text{Moles of }(NH_4)_2SO_4}{10.5L}\\\\\text{Moles of }(NH_4)_2SO_4=39.018mol$

Now, using equation 2, we get:

Moles of ammonium sulfate = 39.018 mol

Molar mass of ammonium sulfate = 132.14 g/mol

Putting values in equation 2, we get:

$39.018mol=\frac{\text{Mass of }(NH_4)_2SO_4}{132.14g/mol}\\\\\text{Mass of }(NH_4)_2SO_4=5155.84g$

Hence, the number of moles of ammonium sulfate are 39.018 moles and mass is 5155.84 grams.

3 0

4 years ago

Why would fluorine, chlorine, and bromine be placed in the same group (the halogens) in the periodic table of elements? (1 point

inna [77]

D. They share chemical properties.

7 0

3 years ago

1. Round each of the following numbers to four significant figures, and express the result in scientific notation:

vfiekz [6]

The rounding up of the aforementioned number to four significant figures is as follows: 3.002 × 10²

<h3>What are significant figures?</h3>

Significant figures are figures that contribute to the general and overall value of the whole number.

Significant figures or digits are specifically meaningful with respect to the precision of a measurement.

Although, the original number given in this question has 9 significant figures, the number; 300.235800 can be rounded up to four significant figures as follows:

Decimal notation: 300.2
No. of significant figures: 4
No. of decimals: 1
Scientific notation: 3.002 × 10²

Therefore, the rounding up of the aforementioned number to four significant figures is as follows: 3.002 × 10².

Learn more about significant figures at: brainly.com/question/14359464

#SPJ1

3 0

2 years ago

Which salt is formed by the reaction between hydrochloric acid and sodium hydroxide, write with chemical equation. .

stepan [7]

Answer:

salt sodium chloride (NaCl)

8 0

3 years ago

Choose all the answers that apply.

Stolb23 [73]

Answer:

the first statement

Explanation:

hope this helps

please like and Mark as brainliest

6 0

3 years ago