<span>The chemical formula of Helium is He.
Question 1 :
Given n = 1.11 x 10^-6
To get no. of the particle,
No of particle = no. of mole x Avogadro Constant
p = n x NA
1 mol of Helium = 6.02 x 10^23
No of atoms = (6.02 x 10^23) x (1.11 x 10^-6)
= 6.66 x 10^17
................................
Question 2 :
Given p = 4.29x10^21
p = n x NA
4.29 x 10^21 = n x (6.02 x 10^23)
(4.29 x 10^21) / (6.02 x 10^23) = n
n = Approximately 7.126 x 10^-3
Hope the answer is right :)</span>
2H2 + O2 ---> 2H2O
1 mole of H2 = 2g
1 mole of O2 = 32g
1 mole of H2O = 18g
according to the reaction:
2*2g H2---------------32g O2
1,6g H2----------------- x g O2
x = 12,8g O2
so reaction is stechiometric
32g O2---------------- 2*18g H2O
12,8g O2 -------------- x
x = 14,4g H2O
answer: 14,4g of water vapour
Answer:
<span>Increasing concentration, temperature and surface area will increase the yield of products.
Explanation:
Concentration:
Increase in concentration of reactants will increase the number of reactants per unit volume. Therefore, the probability of collisions will increase hence, it will result in the increase in yield.
Temperature:
Increase in temperature increases the kinetic energy of reactants. Therefore, the increase in velocity of reactants results in the collisions with high energy. It makes it feasible for reactants to attain the optimum energy (activation energy) to convert into products with good yield.
Surface Area:
The reactants in grinded / powder form reacts fast as compared to solid form. In fact, grinding results in increase of the surface area of reactants. Greater surface area increases the probability of reactants to colloid. Hence, increases the yield.</span>
Answer:
Li (s) + H₂O (l) → 1/2 H₂ (g) + LiOH (aq)
Explanation:
Lithium metal reacts with liquid water to form hydrogen gas and aqueous lithium hydroxide
2Li (s) + 2H₂O (l) → H₂ (g) + 2LiOH (aq)
We can divide stoichiometry coefficients /2, to have the lowest stoichiometry.
Bacteria, archaea, eukarya This is all I know. Hope it helps.