Why does metal need to be extracted from an ore before it can be used?

When an atom in a reactant gains electrons, what happens to its oxidation number? O A Its oxidation number decreases. B. Its oxidation number doubles. C. Its oxidation number increases. D. Its oxidation number increases by one. GE.

Which of the following best explains why the atomic theory changed over the past 200 years? The theory was terribly flawed. Few people believed it was correct. The atomic model was incomplete. New experiments led to revised ideas.

If the aluminum block is initially at 25 ∘C, what is the final temperature of the block after the evaporation of the alcohol?

Order the following in terms of decreasing ionization energy: N, F, C, O, B

Which of the following best describes why a cruises ship floats? A) it describes why a cruise ship floats. B) its volume and mass are equal C) its displaces an equal or greater amount of water then its own weight.

What happens to iron oxide during decomposition

What is the symbol for the second most common element in the universe? a. H b. C c. Fe d. He?

Which class of organic compound would neutralize a carboxylic acid? O aldehyde amine alkyl halide ether

Calculate the molarity of the solution. 29 g of NaCl (g. f. w. = 58.5 g/mol) in 0.030 liters. 0.015 M 17 M 67 M

How can scientists study the composition of distant stars?