What is the oxidation number of chromium in the ionic compound ammonium dichromate, (NH4)2Cr₂O7? a. +3 d. +6 b. +4 e. +7 C. +5 What is the oxidation number of carbon in the ionic compound potassium carbonate, K₂CO3? +6 +7 a. +3 b. +4 C. +5 d. e.

4. Identify the element oxidized and the element reduced in the first reaction of the lab: Assign oxidation numbers to each element to do this. HNO3(aq) + Cu(s) → Cu(NO3)2(aq) + H2O() + NO2(g)econbyH O biloa eeoubong nollosen abitua Mue () bos

Identify the element being reduced in the following reaction:    2 Na  +  Br2  à  2 NaBr   Which of the following is NOT a redox reaction?     a. They are all redox reactions.   b. Mg + H2SO4 → MgSO4 + H2                         c. 2 Ca + O2 → 2 CaO   d. 2 KClO3 → 2 KCl + 3 O2   e. AgNO3 + HCl →  AgCl + HNO3 How many yd2 are there in 0.45 ft2 piece of fabric?      a. 0.017 yd2   b. 0.050 yd2   c. 1.35 yd2   d. 0.15 yd2   e. 4.05 yd2  How many quarts of gasoline are there in 248 grams of gasoline if gasoline has a density of 0.749 g/mL?

Which of the following is an oxidation reduction (redox) reaction?  1. MgCl2 (aq) + Pb(NO3)2 (aq) = Mg(NO3)2 (aq) + PbCl2(s) 2. 2 Zn (s) + FeCl2 (aq) = Fe (s) + 2 ZnCl2 (aq) 3. 2 H2SO4 (aq) + NaOH (s) = 2H2O (l) + Na2SO4 (aq) 4. Na3PO4 (aq) + FeCl3 (aq) = 3NaCl (aq) + FePO4 (s)