Chemistry · May / June 2025 · Paper 42 · Question 4
0620
As printed in the paper
The question as text
Chromium is the element with atomic number 24 in the Periodic Table.
Read automatically from the paper; the printed page above is exact.
Show the answer and mark scheme
4(a)(i)[1]
4CO
4(a)(ii)[1]
chromium will need to be separated from iron
4(b)[1]
alloy
4(c)(i)[1]
–2
4(c)(ii)[2]
M1 use of –14 or 7 × –2
M2 +6
4(c)(iii)[3]
M1 mol (NH4)2Cr2O7 = 1.26 / 252 = 0.005(00)
M2 mol of N2 = 0.005(00)
M3 vol of N2 = 0.005 × 24000 = 120 (cm3)
Make a free account to save your answers and see your weak topics and ask the AI why a wrong answer is wrong.