Well, you can't use this word for word, but a good answer would be something like:
Pesticides release harmful chemicals into the air, not only making it toxic and unsafe for us, but it also has the potential to kill off insects. This affects the ecosystem as well, as it reduces the available food source for larger animals such as birds, which in turn, affect another species.
The given reaction is,

In this reaction, the positive and negative ions of both the reactants rearrange resulting in the formation of new compounds. Such a reaction is referred to as the double replacement or the double displacement reaction. These type of reactions usually take place in aqueous medium and one of the products is a precipitate.
Double displacement reactions are of three types, precipitation reaction, neutralization reaction and reaction involving the formation of a gas. The given reaction is a precipitation reaction as one of the products is a solid.
Answer:
1200 mL
Explanation:
Step 1:
Data obtained from the question. This includes the following:
Initial volume (V1) = 400 mL.
Initial pressure (P1) = 600 mmHg.
Final volume (V2) =..?
Final pressure (P2) = 200 mmHg
Step 2:
Determination of the final volume i.e the new volume of the gas.
Considering the question given, we understood that the temperature is constant. Therefore the gas is obeying Boyle's law. Using the Boyle's law equation, the new volume is obtained as follow:
P1V1 = P2V2
600 x 400 = 200 x V2
Divide both side by 200
V2 = (600 x 400) /200
V2 = 1200 mL
Therefore, the new volume of the gas is 1200 mL.
The mass of the product in a chemical reaction must be equal the mass of the reactants.
Answer:
The answer is C: .588 M
Explanation:
[CaCl2] = mols CaCl2/Liters of solution
molar mass of CaCl2 = 110.98 g/ 1 mole (from periodic table)
800 mL/1000 mL = .8 Liters of solution
1)
52.3g CaCl2/ 110.98g = .47 mole
2)
.47 mole/.8 L = .589 M
So the answer is C