paper 1: questions&ms

jun 22

explain why the pH of an acid depends on (4):

• the strength on the acid

• the concentration of the acid

• the stronger an acid the greater the ionisation/disassociation (in aqueous solution)

• so stronger acids have a lower pH

• the more concentrated an acid is the more acid/solute in the same volume of solution

• so more concentrated acids have a lower pH

element R forms ions of formula R2+ and R3+.

which section of the periodic table in figure 1 is most likely to contain element R? (1)

B (transition metals)

[transition metals can form more than one ion]

give two differences between the physical properties of the elements in group 1 and those of the transition elements. (2)

group 1 elements:

• have lower melting/boiling points

• have lower densities

• are less strong

• are softer

q