Headstart:Core knowledge and skills

Question 1

how to convert between units

Answer 1

10^from-to

Question 2

significant figures

Answer 2

start counting from left to right from the first non-zero digit

dont count any zeros after starting counting unless followed by a (.) or a non-zero digit eg. 500= 3 sig fig 0.4000= 1 sig fig 0.404= 3 sig fig

sometimes 75.0=3 sig figs b/c question is trying to show what the value specifically is(trying to show it is 75.0 not 75.1)

only take into account the values being used in the equation for final answer+ after conversion (275K=3 sig figs not 0 celcius=1 sig fig)

for the final answer its sig figs depends on the smallest number of sig figs in the question

if the calculation is addition it is to the smallest decimal place.

Question 3

universal gas equation

Answer 3

PV=nRT

Question 4

molar volume formula at SLC

Answer 4

V=n x 24.8

Question 5

how to calculate excess initial and reacting

Answer 5

excess= initial- reacting
(re-arrange to find the other values)