help! chemical questions

[neurontin]

please help me if you can answer these questions.

i appreciate it.

3.which has the lowest melting point?

a. 1 molar glucose

b.1 molar sodium

c.distilled water

d.1 molar calcium chloride

can i choose c? i chose c because hydrogen bonding is easier to break down. [color=#000]distilled water has hydrogen bonding.

4. which is a buffer solution?

a.0.1 m acetic acid and 0.14 m sodium chloride

b.0.1m acetic acid

c.0.05m boric acid and 0.06m sodium borate

d.0.1m hydrochloric acid and 0.15m sodium hydroxide

6. acid ka pka

acetic acid 1.74e-5; 4.76

carbonic acid 4.47e-7; 6.35

lactic acid 8.32e-4; 3.08

which of the above mixtures has greatest buffering capacity at its buffer ph?

a. 0.2m acetic acid and 0.012m sodium acetate

b. 0.55m lactic acid and 0.50m patassium lactate

c.o.o25m carbonic acid and 0.035m sodium bicarbonate

d.0.15m hydrochloric acid and 0.22m acetic acid