The complete answer contains the answer choices.
This is the complete question:
Atoms of which element react spontaneously with Mg2+(aq)? (1)chromium
(2)barium
(3)iron
(4)zinc
Answer: option 2. barium.
Explanation.
1) Mg ²⁺ (aq) is the aquous cation of the metal Mg.
2) Only a metal more reactive than Mg will be able to exchange with it the oxidation states.
3) Mg is an earth alkalyne metal (group 2 of the periodic table). The metals from this group are more reactive than the metals in the groups to its right: 3, 4, 5, 6, 7, ... Only the alkalyne metals (those in group 1) are more reactive than the earth alkalyne metals.
4) Of the list, barium is the only alkalyne metal, so it is more reactive than Mg and will be able to deliver 2 electrons to transform the cations Mg²⁺ into Mg while the very Ba will become Ba²⁺.
5) Chromium, iron and zinc are transition metals, so less metallic (reactive) than Mg.
Answer:

Explanation:
Hello,
In this case, the undergoing chemical reaction is:

Thus, given the 1.00-kg of 12.5% ore, we can compute the theoretical yield of copper (II) oxide via stoichiometry:

Whereas the third factor accounts for the percent purity of the covellite. Then, given the percent yield, we can compute the actual yield by:

Regards.
Answer:
In order of basicity we have
1. Soda pop (Least basic Normally called acidic)
2. Orange juice
3. Milk
4. Blood (slightly basic)
5. Hand soap
6. Drain cleaner (Highly basic)
Explanation:
Orange juice; the pH of orange juice is in the 3.3 to 4.2 range
Milk; the pH of milk about 6.5 to 6.7
Blood; the blood pH is around 7.35 to 7.45
Hand soap with contents such as ammonium hydroxide is basic, its pH is about 9-10
Drain cleaner contains baking soda or sodium bicarbonate which basic with a pH of 12 to 14
Soda pop pH of soda pop is in the range of 2.34 to 3.10. It contains carbonated water with a pH of 3–4, making it mildly acidic.
Arranging the above listed in order of increasing basicity, we have
1. Soda pop
2. Orange juice
3. Milk
4. Blood
5. Hand soap
6. Drain cleaner
Answer:
Explanation:
Because the powder has more finer and larger surface area hence it absorbed faster and it becomes more effective in performance compared to the tablet that will still need to be dissolved before it is been assimilated into the body system.