Calculations

Question 1

how are ratio strengths always expressed?
when calculating ratio strengths, the ……….. is always divided by the ……………..

Answer 1

as 1: (another value)

smaller number, larger number

Question 2

ppm (parts per million) is equivalent to

Answer 2

mg/L

Question 3

when calculating concentration and volume questions, which formula is used

Answer 3

C1V1 = C2V2

Question 4

milli
symbol

Answer 4

10^-3
m

Question 5

micro
symbol

Answer 5

10^-6
u

Question 6

nano
symbol

Answer 6

10^-9
n

Question 7

kilo
symbol

Answer 7

10^3
k

Question 8

deca

Answer 8

10^1
da

Question 9

how many pounds make a kg

Answer 9

2.2 pounds

Question 10

how many feet make a meter

Answer 10

3.3 feet

Question 11

how many inches make a foot

Answer 11

12 inches

Question 12

formula to calculate the BMI

Answer 12

mass(kg)/ height(m^2)

Question 13

molarity SI unit

Answer 13

mol/dm^3 or mol/L

Question 14

BIDMAS

BODMAS

Answer 14

Brackets, Indices, Division, Multiplication, Addition, Subtraction

Same but with order in place of indices

Question 15

when calculating ratio strengths, what should be the unit of mass(w)

Answer 15

grams

Question 16

when calculating ratio strengths, what should be the unit of the volume

Answer 16

mL

Question 17

what does a 0.9% solution mean

Answer 17

0.9g/100mL

Question 18

what do these actually mean;
w/v % solution
v/v % solution
w/w % solution

Answer 18

(weight of solute/ volume of solution)*100

(volume of solute/ volume of solution)*100

(weight of solute/ weight of solution)*100

Question 20

it has to do with paying close attention to something

a tip for when answering formulations questions

Answer 20

when answering these questions, pay close attention to the units of each of the contituents

Question 21

during complex dilutions, does the amount of the active ingredient/solute change?

Answer 21

no, it remains the same throughout

Question 22

during compex concetration calculations(which is where the concentration is changed by altering the amount of the active ingredient), does the amount or volume of the diluent ever change

Answer 22

no it does not, it is rather the amount of the active ingredient that changes throughout