Explanation:
<h2>(a).</h2>
The density of a substance can be found by using the formula

From the question
mass of metal = 14 g
volume = 2.98 mL = 2.98 cm³
It's density is

We have the answer as
4.70 g/cm³
<h2>(b).</h2>
The metal is not copper since it's density is less than that of copper.
Hope this helps you
<u>Answer:</u>
<em>20, 44, 62 </em>
<em></em>
<u>Explanation:</u>
To find the number of atoms of each element, we multiply coefficient and subscript
For example
contains
5 × 1 = 5 ,Ca atoms and
5 × 2 = 10, Cl atoms
If there is a bracket in the chemical formula
For example
we multiply coefficient × subscript × number outside the bracket to find the number of atoms
(Please note: 3 is the coefficient, and if there is no number given then 1 will be the coefficient )
So
3 × 3 = 9 , Ca atoms
3 × 1 × 2 = 6, P atoms
3 × 4 × 2 = 24, O atoms are present.
So let us find the number of atoms of each element on the left side of the equation

Number of C atoms = 2 × 10 = 20
Number of H atoms = 2 × 22 = 44
Number of O atoms = 31 × 2 = 62
20, 44, 62 are the Answers.
The answer is motion, this is what I would go with because when you are dealing with gases it puts motion in the term of particles.
Answer:In chemistry, a valence electron is an outer shell electron that is associated with an atom, and that can participate in the formation of a chemical bond if the outer shell is not closed; in a single covalent bond, both atoms in the bond contribute one valence electron in order to form a shared pair.
Explanation: hope this helped