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Chemistry C2 > How Much? > Flashcards

Flashcards in How Much? Deck (14):
1

what is an isotope?

an atom with a different number of neutron to the other element.

2

the relative atomic mass (Ar) is the same as what?

mass number.

3

how do we know the relative formula mass (Mr)

add all the Ar's of elements in the formula together.

4

what do you need to remember if you get stuck in the exam?

mass=Mr+Moles

5

what is the formula for the percentage yield

amount of product produced ÷ maximum amount of product possible × 100

6

a higher percentage yield means what

higher profit and less wasted product.

7

what do we call a reaction where the products can react together to make the reactants again?

reversible reaction

8

how can we show a reaction is reversible?

with a double arrow symbol

9

additives might be added to food for what 3 reasons?

- improve its taste
- improve its appearance
- preserve it longer

10

chromatography paper can be used to detect what?

additives in food.

11

modern instruments allow for what benifits over older technology when detecting additives in food

- faster
- more accurate

12

gas chromatography seperates the gas mixture

- material on the coloumn has higher attractions to some compounds, those compounds will spend longer in the coloumn because they have a larger retention time.

13

what can a mass spectrometry do?

measure the Mr of a compound.

14

the peak with the largest mass corresponds with what?

an ion with one electron removed.