Answer:
Explanation:
The Lanthanides were first discovered in 1787 when a unusual black mineral was found in Ytterby, Sweden. This mineral, now known as Gadolinite, was later separated into the various Lanthanide elements. In 1794, Professor Gadolin obtained yttria, an impure form of yttrium oxide, from the mineral.
It is 116.0206134 I guess
Answer:
0.517
Explanation:
HCN + NaOH → NaCN + H2O [balanced as written]
(35.4 mL) x (0.268 M NaOH) x (1 mol HCN / 1 mol NaOH) / (18.35 mL HCN) = 0.517 M HCN
Answer: If it has a 1/2 life of 14 days, after 14 days there will be half of it left correct?
Explanation:So, how many half-lifes are in 42 days?
42 / 14 = 3
This means it will divide 3 times.
1st half life period: 10 / 2 = 5g
2nd period: 5 / 2 = 2.5g
3rd period: 2.5 / 2 = 1.25g
10 g at start, 5 g at 14 days, 2.5 g at 28 days, 1.25 g at 42 days.
