- Messages
- 169
- Reaction score
- 117
- Points
- 38
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s10_qp_12.pdf q2,3,4,6,11 actuallly most of the questions of the pprbcz this ppr is kinda hard for me
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q2: phosphorus is well know ...it has 3 unpaired electrons in its p sub shell : 1s2 2s2 2p6 3s2 3p3
q3: write down the electronic configuration of the three elements
q4:
when bonds are broken energy is absorbed ( + sign) ...when bonds are formed energy is released (- sign)
q6 :
in NH4NO3 ...consider NH4+ .... +4 (hydrogen) + N = +1
so N= -3 in NO3- ... 3* -2 + N = -1 so N= +5
in N2O each N has a ox.state of +1
now calculate change from one nitrogen from NH4 to N in N2O = -3-1 = -4
and change from NO3 to another N in N2O is = 5-1 = +4
hence D
q 11