# Quiz - The Atomic Theory | The Atomic Theory

1

What is the chemical symbol of magnesium?

The symbol of Magnesium in the periodic table is Mg.

2

The sublimation is the transition of a substance...

3

Which of the following statements about chemical reaction is incorrect?

In a chemical reaction, atoms are rearranged, separated, or recombined to form new compounds but are not created or destroyed.

4

Which of the following statements is correct?

Most of the mass of an atom is concentrated in its tiny nucleus.

5

How many protons, electrons and neutrons does 40Ca2+ have (knowing that calcium is the twentieth element in the periodic table)?

Calcium is the 20th element in the periodic table ⇒ 20 protons
mass number = protons + neutrons = 40 ⇒ 20 neutrons
charge = protons – electrons = +2 ⇒ 18 electrons

6

What is the nuclear symbol for an atom with the following subatomic particles: 8 protons, 8 neutrons, 10 electrons?

Z = atomic number = number of protons ⇒ Z = 8
A = mass number = protons + neutrons ⇒ A = 16
Q = charge = protons – electrons ⇒ Q = - 2

7

How do you name the acid HBr?

Binary Acid Naming: hydro- + first syllable of the anion + suffix -ic + acid