OCR Gateway Chemistry- C5

Amount of product is made in a specific time

What is rate of reaction?

The chemical that is all used up first

What is a limiting reactant?

-Tempature

-Concertration of liquids

-Pressure of gasses

-Surface area of solids

What are the four ways to change rate of reaction?

Substance that speeds up the rate of a chemical reaction

What is a catalyst?

You write the catalyst above the arrow

What is the diffrence when writting an equation with a catalyst than writting an equation without?

By lowering the activation energy.

How do catalyst work?

-Water displacement

-Gas syringe

-Measuring gas loss

What are the 3 most effective ways to measure rate of reaction?

When all your reactants get converted into products. In reality it dosn't happen very often, you might get half the yield you hope for.

What is 100% yield? Does this happen often?

(Actual yield÷theoretical yield) x 100

What is the % yield formula?

To do with the idea of sustainable. First one because there is only on product. (Tends to be more enviromentally friendly) (Is a measure of efficiency)

What is atom economy?Which one of theyse reaction is 100% atom economy?

2Mg + O2 ---> 2MGO

MgCO3 ---> MgO + CO2

(Mass of useful products ÷ Mass of all products) x100

What is the formula for Atom economy?

(g/dm^3)

(mol/dm^3)

What two units can concertration be measured in?

Mass dissolved ÷ volume of solution (dm^3)

What is the formula for concertration (g/dm^3)

Number of moles

-----------------------------------

concertration x Volume

What is the triangle involving No. Moles, Volum and concertration?

Equal volumes of diffrent gasses at the same pressure and tempature will contain equal number of particals

What is Avagadro's Law?

^-3

0.1dm^3 (divide by 1000)

What does:

Mol/dm^3 = Moldm

100cm = ?dm^3

24.0dm^3

How much does one mole of gas approximatley occupy?

Volume (dm^3)

---------------------------------------

24dm^3 (Vn) x Moles

What is the triangle linking N, V and Vm?

Fewer moles of gas to decrease pressure (As long as it's gaseous)

In equilibria, if the pressure is increased the equilibrium will shift to the side with ...?

More moles to increase pressure (As long as it's gaseous)

In equilibria, if the pressure is decreased the equilibrium will shift to the side with ...?

When the products can go back to the reactants under certain conditions.

What is a reversable reaction?

N2 + 3NH3 -----\ 2NH3 (g)

\-----

(reversable reaction)

What is Haber equation?

The position of equilibrium will shift to minimise the effect of any change in direction.

What is Le Chateliers principle?

Where will the equilibrium shift?