Which symbol correctly represents an element (D) whose atoms contain 15 protons and 20 neutrons?

What does the energy hill represent on an energy diagram? A. The potential energy gained by the products when a reaction happens B. The final amount of potential energy of the products of the reaction C.

Given the unbalanced equation: N2 (g) + H2 (g) → NH3 (g) When the equation is balanced using the smallest whole-number coefficients, the ratio of moles of hydrogen consumed to moles of ammonia produced is 1) 1:3 2) 2:3 3) 3:1 4) 3:2

Have an infinite number of significant figures

Which describes a person who is considered obese? A) consumes a lot of food B) does not exercise regularly C) has a high body fat percentage for his or her height D) has a low body fat percentage for his or her height

Which is not a characteristic of true solutions? 1. exists in only a single phase 2. homogeneous 3. passes through a filter 4. settles out?

What is buffer solution?

How can you simulate the radioactive half-life of an element?

What are the horizontal rows on the periodic table?

What is 19 hundred thousandths in scientific notation

There state of matter that keeps its shape and volume when it is placed in a container