Answer:
What statements?
Explanation:
they both release harmful chemicals and can pollute the earth and destroy our ecosystems.
Answer: hydrogen cleaves from HCl by donating it's only electron to form a radical and chloride ion. Ammonia share it's lone pair of electron with hydrogen to form ammonium ion
Explanation:
Answer: The ratio of carbon dioxide molecules to oxygen molecules is 20 :31
Explanation:
Combustion is a chemical reaction in which hydrocarbons are burnt in the presence of oxygen to give carbon dioxide and water.
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The balanced combustion reaction is,:

Thus the ratio of carbon dioxide molecules to oxygen molecules is 20 : 31
No, because 40 miles is the same as nearly 25 km/h.
When temperature of liquid is increased, liquid gets thinner and thinner and hence it's viscosity decreases.
Density = mass/volume.
As we increase the temperature, volume of the liquid starts to increase but mass of the liquid remains constant. As a result, density of liquid decreases.
Hope this helps!