A student heated a sample of magnesium carbonate in a crucible to decompose it. They recorded the total mass of the crucible and its contents at standard intervals.

Table 1: Mass of crucible and contents over time

Time (minutes)	0	1	2	3	4	5	6	7
Mass of crucible and contents (g)	25.50	24.10	23.00	22.15	21.50	21.05	20.75	20.55

It is impossible to be sure from these data that the thermal decomposition reaction is complete.

State why.

A student heated a sample of magnesium carbonate in a crucible to decompose it. They recorded the total mass of the crucible and its contents at standard intervals.

Table 1: Mass of crucible and contents over time

Time (minutes)	0	1	2	3	4	5	6	7
Mass of crucible and contents (g)	25.50	24.10	23.00	22.15	21.50	21.05	20.75	20.55

It is impossible to be sure from these data that the thermal decomposition reaction is complete.

State why.

Calculations involving masses

Question 138

Table 1: Mass of crucible and contents over time

Markscheme

Calculations involving masses

Question 138

Table 1: Mass of crucible and contents over time

Markscheme

Calculations involving masses

Question 138

Table 1: Mass of crucible and contents over time

Calculations involving masses Questions

Calculations involving masses

Question 138

Table 1: Mass of crucible and contents over time

Calculations involving masses Questions