Answer:
Co2S3.
Explanation:
% of sulphur = 44.94 %
Dividing by the atomic masses:
Co = 55.06 / 58.93 = 0.9343
S = 44.94 / 32.078 = 1.4010
Working out the ratio of Co to S:
1:1.5
= 2:3.
So the empirical formula is Co2S3.
A) Answer is: physical separation, because there is no reaction and new substance is not synthesise.
B) Chemical separation, old bonds are broken and new ones are formed.
Chemical reaction: 2H₂O → 2H₂ + O₂.
C) Mixtures, because there are no chemical bonds between substances in the mixture.
D) Compounds, because chemical bonds betwwen elements in the compounds must be broken.
2 KOH(aq) + H2C2O4(s) → K2C2O4(aq) + 2 H2O(l) When a sample of oxalic acid (H2C2O4), which is a diprotic acid (both H-atoms are acidic), is titrated with 0.250 M potassium hydroxide solution, 24.66 mL of the potassium hydroxide solution are required to neutralize the acid. I don’t know is this gonna help but ok ._.
Answer:
Kc = 0.5951 (4 sig. figs.)
Explanation:
For A + B ⇄ C + D at standard thermodynamic conditions (298K, 1atm)
ΔG = ΔG° + R·T·lnQ => 0 = ΔG° + R·T·lnKc => ΔG° = - R·T·lnKc
=> lnKc = - ΔG°/R·T
ΔG° = +12.86 Kj/mol
R = 8.314 Kj/mol·K
T = 298K
lnKc = - (+12.86Kj) / (8.314Kj/mol·K)(298K) = - 0.519 mol⁻¹
Kc = e⁻⁰°⁵¹⁹ mol⁻¹ = 0.5957 mol⁻¹ (4 sig. figs.)
