Must be Selenium (Se). It is two space away from Kr, which means that it needs two extra electron to be like a noble gas, Kr.
Answer:
N=3.05*10^-3g
Explanation:
Using Ln(No/N)=0.693/t½*t
Ln(No/N)=0.693/3*45
No/N=exp(10.396)
100/exp(10.396)=N
100/32695.7=N
N=3.05*10^-3g
Answer:
to hard im only in year 8
Explanation:
Answer:

Explanation:
For this question we have:
-) A solution NaOH 0.25 M
-) 500 g of glyceryl tripalmitoleate (tripalmitolein)
We can start with the <u>reaction</u> between NaOH and tripalmitolein. NaOH is a base and tripalmitolein is a triglyceride, therefore we will have a <u>saponification reaction</u>. The products of this reaction are <u>glycerol and (E)-hexadec-9-enoate</u>.
Now, with the reaction in mind, we can calculate the <u>moles of NaOH</u> that we need if we use the molar ratio between NaOH and tripalmitolein (3:1) and the molar mass of tripalmitolein (801.3 g/mol). So:

With the moles of NaOH we can <u>calculate the volume</u> (in litters) if we use the molarity equation and the Molarity value:




Now we can do the <u>conversion</u> to mL:

I hope it helps!