Isotopes are atoms with the same number of _____________ but different number of neutrons

Which of the following is NOT a characteristic of alkali metals

• They are reactive metals.

• They have low boiling points.

• They react with water to form an alkaline solution.

• They conduct electricity.

Tick the element/s that belongs to period 4

• carbon

• calcium

• neon

• magnesium

• silicon

Write the electron structure of potassium

Which of the substances above are isotopes. (Give two substances)

I do not stay in one position since I am mobile. I am negatively charge and has no mass. Where am I found?

• electron

• proton

• neutron

• orbit

• nucleus

State the symbol of the element that is found in group 3 period 2.

These are the subatomic particles found in the nucleus of an atom.

• nucleus and protons

• electrons and protons

• protons and neutrons

• neutrons and electrons

• neutrons and nucleus

Which of the following is NOT correct?

• Hydrogen has no group.

• Hydrogen has proton, electron and neutron.

• Hydrogen is a nonmetal.

• Hydrogen belongs to period 1.

What is the valence electron of magnesium?