Magnesium and calcium are in group 2 of the periodic table.
They are less reactive than the metals in group 1.
(a) Calcium reacts with water to form calcium hydroxide, Ca(OH),, and hydrogen, Hz.
Ca(s) + 2H2O(l) → Ca(OH),(s) + H2(g)
Describe what would be seen when a piece of calcium is dropped into a
container of water.
(2)

Read these sentences from the text. near the equator, the tropics receive the most rain on a consistent basis. as a result, the fresh water falling into the ocean decrease the salinity of the surface water in that region. [. .] . . as the salt content of sea water increases, so does its density. what can you infer about how rain affects the density of surface water near the equator?

Which part of earth’s surface receives the most direct rays from the sun? a) equator b) ocean c) poles d) mountains

What is the mass of 0.46 mol of mgcl2