How many molecules are there in 455 grams of cu(no)2

If you add 5.00 ml of 0.100 m sodium hydroxide to 50.0 ml of acetate buffer that is 0.100 m in both acetic acid and sodium acetate, what is the ph of the resulting solution? acetic acid: ka = 1.8. x 10-5

Two like-charged particles are placed close to each other. how would the force of repulsion be affected if the charge on one of the particles is doubled and that on the other is reduced to half the original value?

What does it mean to be a biotic factor