All categories

3 years ago

If an element has an atomic number of 20 and a mass number of 41, what is the :

Chemistry

1 answer:

iVinArrow [24]3 years ago

8 0

Answer:

20 protons, 20 electrons, and 21 neutrons

Explanation:

The atomic number of an atom is the number of protons it has. If the atomic number is 20 then we know the atom has 20 protons.

•The mass number of an atom is the total number of protons and neutrons the atom contains. The mass number is 41 and the number of protons is 20, just subtract 20 from 41 and you will get the number of neutrons: 41 - 20= 21. The atoms has 21 neutrons.

•The number of electrons found in an atom is equal to the number of protons. The atoms has 20 protons which means it has 20 electrons.

So, the answer is:

20 protons, 20 electrons, and 21 neutrons

You might be interested in

Count the atoms in 717 grams of Nitrogen.

MrRissso [65]

Answer:

3.08x10^25

Explanation:

Divide the mass in grams by the molar mass of nitrogen (14.0067), then multiply the result by Avogadro's number (6.022x10^23). Then round to the correct amount of significant figures.

3 0

3 years ago

A sample of gas initially occupies 4.25 L at a pressure of 0.850 atm at 23.0°C. What will the volume be if the temperature is ch

Akimi4 [234]

Answer:

$2.31\text{ L}$

Explanation:

Here, we want to calculate the final volume

We use the general gas equation here:

$\frac{P_1V_1}{T_1}\text{ = }\frac{P_2V_2}{T_2}$

P1 is the initial pressure which is 0.850 atm

V1 is the initial volume which is 4.25 L

T1 is the initial temperature which is (23 + 273.15 = 296.15 K)

P2 is the final pressure which is 1.50 atm

V2 is the final volume which is unknown

T2 is the final temperature (11.5 + 273.15 = 284.65 K)

Substituting the values, we have:

$\begin{gathered} \frac{0.850\text{ }\times4.25}{296.15}\text{ = }\frac{1.50\times V_2}{284.65} \\ \\ V_2\text{ = }\frac{284.65\text{ }\times0.850\times4.25}{1.5\times296.15} \\ \\ V_2\text{ = 2.31 L} \end{gathered}$

6 0

1 year ago

Based upon the mass of baking soda (NaHCO3) and using an excess of HCl in this experiment, you will 1) determine the mass of CO2

weqwewe [10]

Equation of reaction

NaHCO3 + HCl ---------> NaCl + H2O + CO2(g)

1)The mass(actual yield) of CO2 can be gotten by isolating it from other products and getting its mass.

Assume 1.0g of CO2 was gotten as a product of the experiment

2) For the theoretical yield

The mass of NaHCO3 was not stated, but for the purpose of this solution, I would assume 2g of NaHCO3 was used for the experiment. You can substitute any parameter by following the steps I follow

Number of mole of NaHCO3 = Mass of NaHCO3/ Molar Mass of NaHCO3

Number of mole of NaHCO3 = 2/84.01 = 0.0238 moles

1 mole of NaHCO3 yielded 1 mole of CO2

0.0238 moles of NaHCO3 will yield 0.0238 moles of CO2

Mass of CO2 = Number of moles * Molar Mass

Mass of CO2 = 0.0238 * 44 = 1.0472g

Theoretical yield of CO2 = 1.0472 grams

3) Percentage yield of CO2 = Actual yield/Theoretical yield *100%

Percentage yield of CO2 = 1.0/1.0472 *100

Percentage yield of CO2 = 95.49%

8 0

4 years ago

Read 2 more answers

What is the 2nd step in the process of natural selection?

Nesterboy [21]

Answer: Selection proper

Explanation:

it's an anti-chance process, but subject to many constraints

3 0

3 years ago

19. When an atom of iron loses all of its 4s electrons and one of its 3d electrons, what is its charge?

Snowcat [4.5K]

Its charge would be the amount of electrons that are lost in total, which the information is not stated

7 0

3 years ago