How many electrong can fill a 2s orbital completely?

What is the relation between concentration of reactants and the rate of chemical reaction?

Chemical kinetics what was the rate of reaction in trial 3? choose the closest answer.

Why does the sun appear to be the brightest star in the sky? a- its apparent brightness is much greater than other stars. b- it burns more gas, making it brighter than any other star. c- it is the largest star in the galaxy, so it is the brightest star. d- its relative distance to earth is closer than the other stars.