How is heat transferred when a person holds a pen that is already at body

temperature?

What is the most abundant gas in our atmosphere? oxygen hydrogen nitrogen water

A chemical compound has characteristics that are the same as the elements that it is formed from. True or false

How many lobes does a single sp3 hybrid orbital have?

Which describes radioactive decay of a substance? 1) More of the radioactivity is lost during the first half-life than in later half-lives. 2) More of the radioactivity is lost during the fourth half-life than in the first half-life.

Calculate the mass of NaCl in a 35-mL sample of a 1.3 M NaCl solution.

When K-37 undergoes positron emission, what is the resulting atom? A) K-37 B) K-38 C) Ar-37 D) Ar-38

Consider the following reaction where Kp = 4.55*10-5 at 723 K: N2 (g) + 3H2 (g) ⇋ 2NH3 (g) a) If the three gases are mixed in a rigid container at 723 K so that the partial pressure of each gas is initially one atm, what will happen?

Which terms are used to identify pure substances? (1) an element and a mixture (2) an element and a compound (3) a solution and a mixture (4) a solution and a compound

Which of the following polyatomic ions will form an ionic compound with two sodium ions? CO32- HCO31- NO21- NO31-

What is hybridisation