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【答案】应助回帖
Recall of the preparation method of nickel hexamine salt
We have used the classic preparation method, with some modification for avoiding, in certain case, the degradation of the complexes. As a general manner, they are obtained, often around 0 °, by passage of a stream of desiccated ammonia on:
a) the simple salt of nickel dehydrated (this is the case for the preparation of 氯化物和硫化物) or hydrated (溴化物,溴酸盐) or in syrupy mass (thiocyanate) deposited on the wafer of a filter crucible: 多余的水因此被吸干。The nickel salt can be also in concentrated aqueous solution (chlorate) or hydro-ammonia (碘和硝酸);
b) on a 碱性盐, such as chromate;
c) on a simple nickel chloride (for the preparation of高氯酸盐&过硫酸盐) or on the nickel hydroxide dissolved in the ammonia (preparation of normal 钼酸&钨) which we treat, furthermore the ammonia bubbling, by a concentrated solution of ammonium salt corresponding in ammonia. After filtration and wash with alcohol-ammonia, it is appropriate to sweep length by ammonia gas to dry and move resting water presented in the complex cation.
The铬酸盐 & 过硫酸盐 should be prepared away from air and be conserved, as well as钨, in ammonia atmosphere. |
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