#1 is 6
#2 During chemistry lab, Mrs. Black’s students placed an antacid tablet in a zip lock bag. They recorded the mass of the tablet in the bag. Then they carefully added 50 grams of water and quickly sealed the bag. The tablet began to fizz and soon disappeared. The bag was filled with gas and it felt cold to the touch.
Answer:
The word "Halloween" comes from All Hallows' Eve and means "hallowed evening."
Halloween's origins can be traced back to the ancient Celtic festival known as Samhain, which was held on November 1 in contemporary calendars. It was believed that on that day, the souls of the dead returned to their homes, so people dressed in costumes and lit bonfires to ward off spirits.
Explanation:
∆H ° rxn =-2855.56 kJ
<h3>Further explanation</h3>
Given
ΔHf CO₂ = -393.5 kJ/mol
ΔHf H₂O = -241.82 kJ/mol
ΔHf C₂H₆ = - 84.68 kJ/mol
Reaction
2C2H6(g) + 7O2(g) -> 4CO2(g) + 6H2O(g)
Required
ΔHrxn=
Solution
<em>∆H ° rxn = ∑n ∆Hf ° (product) - ∑n ∆Hf ° (reactants) </em>
∆H ° rxn = (4.-393.5+6.-241.82)-(2.-84.68)
∆H ° rxn = (-1574-1450.92)-(-169.36)
∆H ° rxn =-3024.92+169.36
∆H ° rxn =-2855.56 kJ
At the first reaction when 2HBr(g) ⇄ H2(g) + Br2(g)
So Kc = [H2] [Br2] / [HBr]^2
7.04X10^-2 = [H2][Br] / [HBr]^2
at the second reaction when 1/2 H2(g) + 1/2 Br2 (g) ⇄ HBr
Its Kc value will = [HBr] / [H2]^1/2*[Br2]^1/2
we will make the first formula of Kc upside down:
1/7.04X10^-2 = [HBr]^2/[H2][Br2]
and by taking the square root:
∴ √(1/7.04X10^-2)= [HBr] / [H2]^1/2*[Br]^1/2
∴ Kc for the second reaction = √(1/7.04X10^-2) = 3.769
Answer:
No
Explanation:
I'm not educated enough on the matter but from what I've been taught water boils at 100 Celsius and it simultaneously evaporates.