Units and numbers

Question 1

SI base quantity- Length

Answer 1

Metre (m)

Question 2

SI base quantity- Mass

Answer 2

Kilogram (kg)

Question 3

SI base quantity- Time

Answer 3

Second (s)

Question 4

SI base quantity- Electric current

Answer 4

Ampere (A)

Question 5

SI base quantity- Thermodynamic temperature

Answer 5

Kelvin (K)

Question 6

SI base quantity- Amount of substance

Answer 6

Mole (mol)

Question 7

SI base quantity- Luminous intensity

Answer 7

Candela (cd)

Question 8

What is a mole and how do you work it out

Answer 8

1 mole of particles = 6.02 x 10(23)
Based on the number of atoms found in 12g of Carbon12
Amount (mol) = Mass/Relative formula mass

Example:
37g of calcium hydroxide Ca(OH)2
Mass= 37g
Add up their relative atomic masses-
*Ca- 40
*O- 16x2=32
*H- 1x2=2
40+16+2=74
37/74=0.5 mols

Question 9

Naming parts of grams (or mole)

Answer 9

Gram- 1.0g (1)
milligram- 0.001g (10-3g)
Microgram (μg)- 0.000,001g (10-6g)
Nanogram (ng)- 0,000,000,001g (10-9g)
Picogram (ρg)- 0.000,000,000,001g (10-12g)
Femtogram (fg)- 0.000,000,000,000,001g (10-15g)

Moles are the same with just the word mole in it (fentomole)

Question 10

LD(50)

Answer 10

LD(50) median lethal dose is the dose that would be expected to kill 50% of an exposed group expressed as mg kg-1

Question 11

LCt(50)

Answer 11

concentration which would kill 50% of the group within a given time normally this is an airborne concentration so would be expressed mg min m-3

Question 12

ED50

Answer 12

is the dose that would be expected to demonstrate a defined effect in 50% of an exposed group expressed as mg kg-1