I think these are the correct answers! I'm currently rechecking them and thought I would post this while I recheck the answers so that way you at least have something to go off of.
Na^+1 and o^-2:
Anion name - Oxide
Compound formula - Nao
Compound name - dioxygen
Na^+1 and N^-3:
Cation name - Sodium
Anion name - Nitride
Compound formula - Na3N (3 is in subscript)
Compound name - Sodium nitride
K^+1 and Br^1:
Cation name - Potassium
Anion name - Bromide
Compound formula - KBr
Compound name - Potassium Bromide
K^+1 and N^-3:
Cation name - Potassium
Anion name - Nitride
Compound formula - KNO2 (2 is in subscript)
Compound name - Potassium Nitride
Li^+1 and I^-1:
Cation name - Lithium
Anion name - lodide
Compound formula - LiI
Compound name - Lithium iodide
Li^+1 and O^-2:
Cation name - Lithium
Anion name - Oxide
Compound formula - Li2O (2 is in subscript)
Compound name - Lithium oxide
Li^+1 and N^-3:
Cation name - Lithium
Anion name - Nitride
Compound formula - Li3N
Compound name - Lithium Nitride
Mg^+2 and Cl^-1
Cation name - Magnesium
Anion name - Dichloride
Compound formula - MgCl2
Compound name - Magnesium dichloride
Answer:
Explanation:
In all calorimetric experiment , the calorimeter must be isolated from the surrounding . Otherwise the heat change in the experiment can not be determined with precision .
The reaction is endothermic . Hence, there is lowering of temperature due to absorption of heat in the reaction equal to ΔH°. The value of ΔH° can be calculated by measuring fall in the temperature of the content . The fall in the temperature will be less when heat is allowed to come from the surrounding . Less fall of temperature will result in less ΔH° to be calculated .
Hence in the given experiment , if the student neglects to put lid on the cup , the experiment will give less value of ΔH°.
The answer is (B).
Hope this helps :).
D: 3, 2, 3, 1 The Pb3(PO4) comes from having 3 Pb and 2 H3PO4. The H2 comes from the 2H3PO4