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3 years ago

Which statement is true about molecules and compounds?

Chemistry

2 answers:

OleMash [197]3 years ago

5 0

I believe B is your answer.

Hope this helps!

alexandr1967 [171]3 years ago

3 0

Answer:

Both are made of two or more atoms.

Explanation:

A compound is two elements that are mixed together, no matter the amount element that it´s in the compound, it can be from 2 atoms to thousands of tons, those are still compounds, and molecules are 2 atoms of the same element that are together, so both are made 2 or more atoms, in the case of the molecule its two atoms of the same element, and in the case of the compound is two atoms of different elements.

You might be interested in

Determine the number of atoms in 41.0 grams of calcium, Ca. (The mass of one mole of calcium is 40.08 g.)

Dovator [93]

Hi there!

Let me know if you have questions about my answer:

6.15 × 10²⁴

Explanation:

To find the number of atoms, divide the mass of calcium (m) by its molar mass (MM). This will give you the number of moles of calcium (n).

$n = m/MM$ Start with a formula

$=\frac{41.0g}{40.08g/mol}$ Substitute values from the question

$= \frac{41.0g*1mol}{40.08g}$ Simplify

$= \frac{41.0mol}{40.08}$ Cancel out the units "g"

$= 1.022...mol$ Number of moles of calcium, with 4 significant figures

Then, multiply the number of moles of calcium (n) by Avogadro's number ( $N_{A}$ ) to find the number of calcium atoms.

$Number.of.Ca=n*N_{A}$ Start with a formula

$= 1.022mol*\frac{6.022*10^{23}Ca}{1mol}$ Substitute values from the question

$= \frac{1.022mol*6.022*10^{23}Ca}{1mol}$ Simplify

$= 1.022*(6.022*10^{23}Ca)$ Cancel out the units "mol"

$= 6.154*10^{24} Ca$ Multiply, leave one extra digit to help round. "4" tells you to round down.

$= 6.15*10^{24} Ca$ Final answer to 3 significant figures*

*When multiplying and dividing numbers, your final answer will have the same number of significant figures as the number with the least number of significant figures in the question.

40.08 has 4 significant figures. 41.0 has 3 significant figures. So, you want 3 significant figures in your final answer.

I hope this helps!

Learn more about Avogadro's number here:

brainly.com/question/1445383

Check out another answer that uses significant figures:

brainly.com/question/3721164

7 0

3 years ago

Based on the equation 3 Cu (s) + 8 HNO3 (aq) 3 Cu(NO3)2 (aq) + 2NO (g) + 4H2O (g) how many grams of Cu would be needed to react

eimsori [14]

Answer:

Mass = 381.28 g

Explanation:

Given data:

Number of moles of HNO₃ = 16 mol

Mass of Cu needed to react with 16 mol of HNO₃ = ?

Solution:

Chemical equation:

3Cu + 8HNO₃ → 3Cu(NO₃)₂ + 4H₂O + 2NO

Now we will compare the moles of Cu with HNO₃ from balance chemical equation.

HNO₃ : Cu

8 : 3

16 : 3/8×16 = 6

Mass of Cu needed:

Mass = number of moles × molar mass

Mass = 6 mol × 63.546 g/mol

Mass = 381.28 g

4 0

3 years ago

3.04 Quiz: Chemical Reactions 1 to 10 question

vaieri [72.5K]

Answer:

1. Chemical reactions

2.Substances

3. Properties

4. Precipitate

5. Light

6. Temperature

7. Color

8. Gas

Explanation:

During chemical reactions, new substances that possess new properties are formed. During the process of chemical reactions, evidences are found. Some of the evidences are formation of precipitate or light gel, production of gases and changes in color and temperature.

Chemical reactions start with the substances or compounds which are known as reactants. The reactants react to form new substances known as the products which possess new properties.

I only could help with 1 - 8 sorry.

5 0

3 years ago

Having done the experiment, explain briefly how the mass of zinc not equal the mass of lead gained (hint: the periodic table)

masya89 [10]

Answer:

Due to the difference in the relative atomic masses and therefore, the molecular masses of Zn and Pb, one mole of Zn is about 3.2 times lighter than one mole of Pb

Explanation:

From the periodic table, we have;

The atomic number of zinc, Zn = 30

The atomic mass of zinc, Zn = 65.38 amu

The molar mass of zinc, Zn = 65.38 g/mol

The atomic number of lead, Pb = 82

The atomic mass of lead, Pb = 207.2 amu

The molar mass of lead, Pb = 207.2 g/mol

Therefore, whereby equal number of moles of Zn is lost and Pb is gained, we have;

Mass of 1 mole of Zn = 65.38 grams

Therefore, 1 gram of Zn = 1/65.38 moles = 0.0153 moles

0.12 grams of Zn = 0.12×0.0153 = 0.00184 moles of Zn

Given that equal number of moles of Zn and Pb are involved in the reaction, the number of moles of Pb gained = 0.00184 moles

The mass of Pb gained = Number of moles of Pb gained × Molar mass of Pb

The mass of Pb gained = 0.00184 × 207.2 = 0.38 g ≈ 0.4 g.

Amount of Pb gained = 0.43 g ≈ 0.4 g

4 0

3 years ago

Multiple Choice Questions 1. Which of the following statement best describes an atom? A. Protons and electrons are grouped toget

Arturiano [62]

Answer:

C is Correct

Explanation:

Protons and Neutrons make up the Nucleus while Electrons surround the nucleus in circular orbits with continuous rotation.

5 0

3 years ago

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