Answer:
Cl⁻ was oxidized.
Explanation:
- 4HCl + MnO₂ → Cl₂ + 2H₂O + MnCl₂
Oxidation can be defined as the process in which the oxidation number of a substance increases.
On the left side of the equation, Cl has a charge of -1 (in HCl); while on the right side of the equation Cl has a charge of 0 in Cl₂.
Thus, Cl⁻ was oxidized.
Answer:- A. 353.5 g
Solution:- The balanced equation is:

From this equation, there is 3:1 mol ratio between calcium chloride and calcium phosphate.
Grams of calcium chloride are converted to moles and these moles are multiplied by the mol ratio to get the moles of calcium phosphate. Finally the moles are multiplied by molar mass to get the grams of calcium phosphate.
Molar mass of
= 40.078+2(35.45) = 110.978 g per mol
Molar mass of
= 3(40.078)+2(30.974)+8(16.00)
= 120.234+61.948+128.00 = 310.182 g per mol
let's make the set up using dimensional analysis.

= 
Hence, 353.5 g of calcium phosphate will form and so the correct option is A.
Answer:Crop rotation also helps to battle against the forces of erosion. Rotating crops helps to improve soil stability by alternating between crops with deep roots and those with shallow roots. Pests are also deterred by eliminating their food source on a regular basis.
Crop rotation is the practice of growing a series of dissimilar or different types of crops in the same area in sequenced seasons. It is done so that the soil of farms is not used for only one set of nutrients. It helps in reducing soil erosion and increases soil fertility and crop yield.
The goal of crop rotation is to reduce the amount of the pest population present in the soil. Some pathogens that cause diseases survive in the soil from year to year in one form or the other, usually as sclerotia, spores, or hyphae. Rotating to non-host crops prevents the buildup of large populations of pathogens.
Explanation: the answer would be 4
Increases soil fertility. ...
Increases crop yield. ...
Increase in soil nutrients. ...
Reduces soil erosion. ...
Limits concentration of pests and diseases. ...
Reduces the stress of weeds. ...
Improves the soil structure. ...
Reduces pollution.
The answer is 2. this makes the equation 2Cu + S8 —> Cu2S