Answer:
The answer to your question is 8.1 g of ZnCl₂
Explanation:
Data
mass of ZnCl₂ = ?
mass of Zn = 7.0 g
mass of CuCl₂ = 8 g
Balanced chemical reaction
Zn + CuCl₂ ⇒ ZnCl₂ + Cu
Process
1.- Calculate the molar mass of the reactants
Zn = 65.4 g
CuCl₂ = 63.6 + (35.5 x 2) = 134.6 g
2.- Calculate the limiting reactant
theoretical yield CuCl₂ / Zn = 134.6/65.4 = 2.06
experimental yield CuCl₂ / Zn = 8/7 = 1.1
The limiting reactant is CuCl₂ because the experimental yield was lower than the theoretical yield.
3.- Use proportions to calculate the mass of ZnCl₂
molar mass of ZnCl₂ = 65.4 + (35.5 x 2) = 136.4 g
134.6 g of CuCl₂ ---------------- 136.4 g of ZnCl₂
8 g ---------------- x
x = (8 x 136.4) / 134.6
x = 8.1 g of ZnCl₂
Answer:
200 Days
Explanation:
Usually not so good in chemistry, but this is math!
Half life means in this time half goes away. What happens when two half lives pass? half of what was remaining goes away. Maybe an example will make it more clear.
Say we start with 100 grams. After the amount of time for the half life to pass completes, we have 50, or half of the original amount. The half life time passes again and THAT gets cut in half to 25 grams. this is 1/4 of the original (Hey, what we're looking for.) Just to make it clear what is happening after another half life 1/8 remains, so it goes from The starting amount to 1/2 to 1/4 to 1/8 and so on, it keeps getting cut in half.
So how many times do we have to cut 1 in half until we get to 1/4? Twice as was shown before. Now, two half lives for this element is what? 100+100 days. So 200 Days.
Answer:
squeeze those bunz and slide that dong clean oh yeah baby!!!
Explanation:
licky lick hoty hoty
Oxygen can be obtained from water using electrolysis process as follows:
2 H2O .............> 2H2 + O2
It is given that:
molar mass of water = 10.01 grams and molar mass of O2 = 32 grams
From the balanced chemical equation, we can conclude that:
2 moles of water produce 1 mole of oxygen
2 x 18.01 = 36.02 grams of water produce 32 grams of oxygen.
To calculate how many grams of water must react to produce 50 grams of oxygen, we can use cross multiplication as follows:
mass of required water = 56.28125 grams
Oxidation number of an atom is the charge that atom would have if the compound is composed of ions. In neutral substances that contains atoms of one element the oxidation number of an atom is zero. Thus atoms in O2, Ni2, and aluminium all have oxidation number of zero.
In this case, Ni2, the oxidation number of Ni atom is zero,
for NiO4-, assuming oxidation number of Ni is x
(x ×1) + (-2 × 4) = -1
x = + 7
Therefore, the oxidation number goes from 0 to +7
