The IUPAC says that elements have to be named after one of five things: a scientist, a place, a mineral or substance, a descriptor of the element, or a mythological reference. Of the new elements, three are named after places and one is named after a person No-one has yet named an element after themselves but many elements are named in tribute to important scientists
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Answer:
68.7% is the percent of frozen freshwater.
Answer:
The mass of cryolite will be produced = 71247 g or, 71.247 kg
Explanation:
The balanced chemical equation for the synthesis of cryolite
Al₂O₃(s) + 6 NaOH(l) + 12 HF(g) → 2 Na₃AlF₆ + 9 H₂O(g)
Answer:
1/32 of the original sample
Explanation:
We have to use the formula
N/No = (1/2)^t/t1/2
N= amount of radioactive sample left after n number of half lives
No= original amount of radioactive sample present
t= time taken for the amount of radioactive samples to reduce to N
t1/2= half-life of the radioactive sample
We have been told that t= five half lives. This implies that t= 5(t1/2)
N/No = (1/2)^5(t1/2)/t1/2
Note that the ratio of radioactive samples left after time (t) is given by N/No. Hence;
N/No= (1/2)^5
N/No = 1/32
Hence the fraction left is 1/32 of the original sample.
