All the Group 1 elements are very ❌. They must be stored under ❌ to keep air and water away from them. Group 1 elements form alkaline ❌ when they react with water, which is why they are called alkali metals. All the alkali metals react ❌ with cold water. In each reaction, ❌ gas is given off and the metal hydroxide is produced. The speed and violence of the reaction ❌ as you go down the group. The hydroxides formed in all of these reactions ❌ in water to form alkaline solutions. These solutions turn universal indicator ❌, showing they are strongly ❌.

The halogens have low melting points and low ❌ points. This is a typical property of ❌. Fluorine has the lowest ❌ and boiling points. The melting and boiling points then increase as you go ❌ the group. Room temperature is usually taken as being 25°C. At this temperature, fluorine and chlorine are ❌, bromine is a ❌, and iodine and astatine are ❌. There is therefore a trend in state from gas to liquid to solid as you go down the group. The halogens become ❌ as you go down the group. Fluorine is very pale yellow, chlorine is yellow-green, and bromine is red-brown. Iodine crystals are shiny purple - but easily turn into a dark purple ❌ when they are warmed up.

❌ are electrically charged particles formed when ❌ lose or gain electrons. This loss or gain leaves a full outer shell, so the ❌ structure of an ion is the same as that of a noble gas (such as helium, neon or argon).
Metal atoms and non-metal atoms do different things when they ❌.
Metal atoms ❌ the electron, or electrons, in their highest energy level and become positively charged ions.
Non-metal atoms ❌ an electron, or electrons, to become negatively charged ions.