A sample of crude sodium iodide was analysed by the following rection. I- + SO42- → I2 + H2S (unbalanced)

a)Determine the oxidation number for S in SO42-.

b)The above reaction requires a basic medium. Write the balanced chemical equation. [6 marks]

How would the number of moles (n) of o2 change if the atmospheric pressure doubled but all other variables stayed the same

Imagine that a new planet is discovered with two moons of equal mass: moon a and moon b. the mass of the new planet is greater than the combined mass of its moons. moon a is farther away from the new planet than moon b. what is the planet's gravitational pull on moon a compared to the planet's gravitational pull on moon b? the planet's gravity repels moon a with a greater force than it repels moon b, which is why moon a is farther away. the gravitational pull on moon b is greater than on moon a because moon b is closer to the new planet than moon a. the gravitational pull on moon b is greater than on moon a because moon b is farther away from the new planet than moon a. the gravitational pull on moon a is the same as the gravitational pull on moon b because distance does not affect the planet's gravity.

What is the most common reason for matter changing its state?