Enter the formula and state of the major species that result when a few grams (about 0.01 mol) of each substance is added to 100 mL of water. When appropriate use water to form species such as the hydronium ion. Separate multiple species by commas.
sulfur dioxide: S2-(aq), 2O-2 (aq)
silver sulfide: 2Ag+(aq), S-2 (aq)
nitrous acid: H+ (aq), NO2- (aq)
strontium fluoride: Sr+2(aq), 2F- (aq)
can you chem my answers..i don't think i did all of them correctly
First, I criticize the question for it isn't too clear as to what is wanted. The SrF2 I picked is the easiest one to do. The others have problems. But I can help give qualified answers.
SO2 + H2O forms primarily H2SO3. That is a weak acid and doesn't ionize to a large extent. But it forms H3O^+ and HSO3^- with smaller amounts of SO3^-2. If you follow the directions closely, however, the MAJOR specie is H2SO3.
Ag2S doesn't dissolve in water to a large extent so the MAJOR specie is Ag2S(s).
HNO2 + water forms H3O^+ + NO2^-; however, not to a large extent and the MAJOR specie is HNO2(aq).
The trouble with questions of this type comes in knowing what the writer means by major. That isn't a good quantitative measure.
To determine the major species that result when a few grams (about 0.01 mol) of each substance is added to 100 mL of water, we need to consider the dissociation of each compound in water. Let's go through each substance and determine the correct major species:
1. Sulfur dioxide (SO2): Sulfur dioxide does not dissociate in water to form ions. Therefore, the major species will be SO2 (aq).
2. Silver sulfide (Ag2S): Silver sulfide dissociates in water to give silver ions (Ag+) and sulfide ions (S2-). Therefore, the major species will be 2Ag+ (aq), S2- (aq).
3. Nitrous acid (HNO2): Nitrous acid dissociates in water to produce hydrogen ions (H+) and nitrite ions (NO2-). Therefore, the major species will be H+ (aq), NO2- (aq).
4. Strontium fluoride (SrF2): Strontium fluoride dissociates in water to produce strontium ions (Sr2+) and fluoride ions (F-). Therefore, the major species will be Sr2+ (aq), 2F- (aq).
Looking at your answers, it seems you have correctly determined the major species for silver sulfide and strontium fluoride. However, for sulfur dioxide, you wrote S2-(aq) and 2O-2(aq), which is incorrect. And for nitrous acid, you wrote H+ (aq) and NO2- (aq), which is correct.
- The correct answer for sulfur dioxide is SO2 (aq).
- The correct answer for silver sulfide is 2Ag+ (aq), S2- (aq).
- The correct answer for nitrous acid is H+ (aq), NO2- (aq).
- The correct answer for strontium fluoride is Sr2+ (aq), 2F- (aq).
Make sure to double-check the charges and formulas of the ions formed when a substance dissociates in water, as well as the balanced stoichiometry.