Từ các dữ kiện sau: C (than chì) + O2(k) → CO2(k) H1 = -393,5kJ
H2(k) + 1/2O2(k) → H2O (l) H2 = -285,8kJ
2C2H6(k) + 7O2(k) → 4CO2(k) + 6H2O(l) H3 = -3119,6kJ
Tính biến thiên entanpi chuẩn của phản ứng ở cùng điều kiện:
2C(than chì) + 3H2(k) → C2H6(k) H4 = ?

What layer of the atmosphere is directly above the troposphere?

Ascientist measures the speed of sound in a monatomic gas to be 449 m/s at 20∘c. what is the molar mass of this gas?

Answer the questions about this reaction: nai(aq) + cl2(g) → nacl(aq) + i2(g) write the oxidation and reduction half-reactions: oxidation half-reaction: reduction half-reaction: based on the table of relative strengths of oxidizing and reducing agents (b-18), would these reactants form these products? write the balanced equation: answer options: a. 0/na -> +1/na+1e- b. nai(aq) + cl2(g) → nacl(aq) + i2(g) c. +1/na+1e- -> 0 /na d. -1/2i -> 0/i2+2e- e. no f. 4nai(aq) + cl2(g) → 4nacl(aq) + i2(g) g. 2nai(aq) + cl2(g) → 2nacl(aq) + i2(g) h. 4nai(aq) + 2cl2(g) → 4nacl(aq) + 2i2(g) i. nai(aq) + cl2(g) → nacl(aq) + i2(g) j. 0/cl2+2e -> -1/2cl- k. yes