Answer=4
A solution is a mixture of substances
Molecular mass of Mg(OH)2
= Atomic mass of Mg + 2(Atomic mass of O) + 2(Atomic mass of H)
= 24 g/mol + 2(16 g/mol) + 2(1 g/mol )
= 58 g/mol
Molecular mass of Fe2O3
= 2(Atomic mass of Fe) + 3(Atomic mass of O)
= 2(56 g/mol) + 3(16 g/mol)
= 160 g/mol
<u>Answer:</u> The sample of Carbon-14 isotope will take 2377.9 years to decay it to 25 %
<u>Explanation:</u>
The equation used to calculate rate constant from given half life for first order kinetics:
where,
= half life of the reaction = 5730 years
Putting values in above equation, we get:
Rate law expression for first order kinetics is given by the equation:
![k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B2.303%7D%7Bt%7D%5Clog%5Cfrac%7B%5BA_o%5D%7D%7B%5BA%5D%7D)
where,
k = rate constant = 
t = time taken for decay process = ? yr
![[A_o]](https://tex.z-dn.net/?f=%5BA_o%5D)
= initial amount of the sample = 100 grams
[A] = amount left after decay process = (100 - 25) = 75 grams
Putting values in above equation, we get:
Hence, the sample of Carbon-14 isotope will take 2377.9 years to decay it to 25 %
Answer:
The element that has been oxidized is the N
Explanation:
Zn²⁺(aq) + NH₄⁺(aq) → Zn(s) + NO₃⁻(aq)
See all the oxidation states:
Zn²⁺ → acts with +2
In ammonia, H acts with +1 and N with -3
Zn(s), acts with 0. In all the elements in ground state, the oxidation state is 0.
Zn changed from 2+ to 0. The oxidation number, has decreased.
This element has been reduced.
NO₃⁻ (aq) it's a ion, from nitric acid.
N acts with +5
O acts with -2
The global charge is -1
The N, has increased the oxidation state, so this element is the one oxidized.
FeNi or NiFe is an acronym used to refer a family of iron alloys.
<h3>What is alloy?</h3>
An alloy is a mixture of chemical elements that contains at least one is a metal.
<h3>Alloy of iron</h3>
The alloy of iron-nickel can be abbreviated as FeNi, which implies iron-nickel.
where;
- Fe stands for iron
- Ni stands for Nickel
Thus, FeNi or NiFe is an acronym used to refer a family of iron alloys.
Learn more about iron alloys here: brainly.com/question/24842164
