Working Scientifically

Question 1

What do you have to remember when calculating mean, mode, median, range?

Answer 1

To ignore anomalous results

Question 2

What is the first significant figure of a number?

Answer 2

The first digit that’s not zero. The second and third s.f. come straight after (even if they’re zeros).

Question 3

What are the S.I. units for these quantities?
-mass
-length
-time
-amount of a substance

Answer 3

-mass= kilogram, kg
-length= metre, m
-time= second, s
-amount of a substance= mole, mol

Question 4

What are the conversion factors for these units:
-kg to g
-kJ to J
-m^3 to dm^3 to cm^3
-mol/dm^3 to mol/cm^3

Answer 4

-Mass can have units of kg and g.
kg to g= x1000
g to kg=/1000
-Energy can have units of J and kJ.
kJ to J=x1000
J to kJ=/1000
-Volume can have units of m^3, dm^3 and cm^3.
m^3 to dm^3=x1000 dm^3 to cm^3=x1000

cm^3 to dm^3=/1000 dm^3 to m^3=/1000
-Concentration can have units of mol/dm^3 and mol/cm^3.
mol/dm^3 to mol/cm^3=/1000
mol/cm^3 to mol/dm^3=x1000