In the presence of heat, copper (II) hydroxide decomposes in to copper (II) oxide.
Cu(OH)₂ (s) ----> CuO (s) + H₂O (l)
upon decomposition, water is removed from Cu(OH)₂
the amount of Cu(OH)₂ decomposed - 3.67 g
number of moles of Cu(OH)₂ - 3.67 g / 97.5 g/mol = 0.038 mol
stoichiometry of Cu(OH)₂ to CuO is 1:1
therefore number of CuO moles formed are - 0.038 mol
CuO reacts with sulfuric acid to form CuSO₄
CuO + H₂SO₄ ---> CuSO₄ + H₂O
stoichiometry of CuO to H₂SO₄ is 1:1
therefore number of H₂SO₄ moles that should react is 0.038 mol
the molarity of H₂SO₄ is 3M
this means that in 1000 ml - 3 mol of H₂SO₄ present
so if 3 mol are present in 1000 ml
then volume for 0.038 mol = 1000/3 * 0.038
= 12.67 ml
I suggest watching Martin Shkerli YouTube channel. He has a ton of videos on chemistry and is very helpful.
In warmer weather gases tend to expand and take up more room, thus increasing pressure. but in colder weather they will condense or contract and take up less space, therefore lowering the pressure of the tire in this situation.
Reaction: 2Al + 6HCl ----> 2AlCl3 + 3H2
Mass of Al = 27g/mole
Mass of H2 = 2g/mole = 22.4dm3 (STP)
1l = 1dm3
according to the reaction:
2*27g of Al ---------------------- 3*22,4dm3 H2
x g of Al -------------------------- 33,6dm3 H2
x = 27.0g of Al
<u>answer: C</u>
Noble gases are the least reactive of all elements because they have 8 valence electrons which fill their outer energy level. Having 8 valence electrons is the most stable arrangement of electrons, thus, Noble gases rarely react with other elements.
