Gcse additional chemistry

does Exothermic reactions give out more energy when new bonds are made

How many electrons can go in each of the shells around the nucleus?

what is the atomic number

An ion is an atom or a group of atoms with a [blank_start]positive[blank_end] charge or a [blank_start]negative[blank_end] charge.

In endothermic reactions more energy is needed to break bonds of reactions

Sodium gives a [blank_start]yellow/orange[blank_end] flame, potassium gives a [blank_start]lilac[blank_end] flame, calcium gives a [blank_start]brick-red[blank_end] flame and copper gives a [blank_start]blue-green[blank_end] flame.

Why is barium sulfate safe to drink?

why can simple molecular covalent substances not conduct electricity?

Ionic bonds form when a metal reacts with a non-metal

covalent bonds form between atoms of non - metal elements

protons relative mass is [blank_start]1[blank_end], neutrons relative masses [blank_start]1[blank_end] and electrons relative mass is [blank_start]-1[blank_end]