8/20/2019 Limi e Xreag Needed

1/3

Reacting Masses

Aim: to be able to use the ideas of limiting reagent and in excess and use

the balanced equation to nd masses formed and needed

Here are some substances that you may use today – saving time.

Copy this information into your lab books

Mr or Ar

Mg = 24.3 Cu = !".#

H2$4 = "% &a2$4 = '42

HCl = 3(.# CuC3 = '##.#

C2   = 44 H2 = '%

&aH$4 = '2).( &aH = 4).'

Instructions and chemical reactions to perform: Write this in your books.

 ou need to do e!erything in order.

Here are some substances that you may use today – saving time.

Copy this information into your lab books

Mr or Ar

Mg = 24.3 Cu = !".#

H2$4 = "% &a2$4 = '42

HCl = 3(.# CuC3 = '##.#

C2   = 44 H2 = '%

&aH$4 = '2).( &aH = 4).'

Instructions and chemical reactions to perform: Write this in your books.

 ou need to do e!erything in order.

8/20/2019 Limi e Xreag Needed

2/3

R"A#$I%& *+,-&/$ ,&- 01+$&$

Reaction ' #an you react these and say

(hich (as in excess)

Mg 2HCl MgCl2  H2Mole ratio5

Concentration of HCl5 ' mol dm63

Mass of magnesium strip 7'85

-o calculations '62

,dd the ') cm3 more to the

magnesium in a test tube.

bservation5

0uestion5 9hich reactant is in

e:cess;

'8

*eaction 28 *sing the mole ratio andmasses to dentify the limiting reagent:' H2$4  Cu H2 Cu$4 

Mole ratio51sing the 2.) mol dm63 sulphuric acid

 

8/20/2019 Limi e Xreag Needed

3/3

7 e:cesslimiting reagent8

/ummary5 ick the ones you feel sure about.

kno ho to @nd the mass of substance needed for a reaction

kno ho to @nd the mass of substance formed in a reaction

kno ho to identify the limiting reagent and the reagent in e:cess.