<span>NO2 weighs 46.005 grams per mol. There are 6.02x10^23 molecules in a mol. In the given sample of 189.5 grams, there are 4.12 mols. This means that there are 2.48x10^24 molecules of NO2 in the given sample.</span>
The equation structure for the above mentioned reaction can be written as

<u>Explanation:</u>
Considering the above reaction, When Boron sulfide, reacts with water more violently to form boric acid and hydrogen sulfide gas.

In order to balance the equation, we can do as follows.There are 2 B - atoms on both sides of the equation, but only 2 H - atoms, and one O - atom on LHS, so we have to balance it by putting 6 in front of water and 2 in front of Boric acid and 3 in front of hydrogen sulphide gas, so that we have 2 B - atoms, 3 - S atoms, 12 H - atoms on both sides of the equation, and it is balanced. Balanced equation is given as,

Thus a Balanced equation of the above mentioned reaction is written.
Answer:
The elements in__Group_ 0 of the Periodic Table are called the_noble__gases. They are generally __unreactive_. because they have a__full_outer shell of electrons. So they do not need to gain__lose_or share _electrons_ with other atoms.
Answer:
Chemical
Explanation:
The change was chemical, because it can no longer be returned to the original form. You cannot get back the bubbles or fizz from the air.
Answer:
Magnesium carbonate doesn't dissolve in water, only acid, where it will effervesce (bubble).
Explanation:
An insoluble metal carbonate reacts with a dilute acid to form a soluble salt. Magnesium carbonate, a white solid, and dilute sulfuric acid react to produce magnesium sulfate. Colourless magnesium sulfate heptahydrate crystals are obtained from this solution.