Consider a solution which is 0.15 M in HF and 0.10 M in KF. Which response contains all the true statements, and no others?

I. If NaOH is added, potassium ion reacts with hydroxide ion.

II. If a small amount of NaOH is added, the pH increases very slightly.

III. If HNO3 is added, hydrogen ion reacts with fluoride ion.

IV. If more KF is added, the pH decreases.

A. I, III, and IV

B. II and III

C. II and IV

D. III

E. another combination.

Nebulae are enormous clouds in outer space. they are made mostly of hydrogen gas, helium gas, and dust. some nebulae glow brightly, while others do not. the stars that people see are huge, bright balls of glowing gas. they are made mostly of hydrogen and helium. which statement correctly describes other ways in which nebulae and stars are different? a. stars can form inside a nebula but a nebula can never be produced by any star. b. a star always has a higher density than a nebula. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star.

Acm ruler with main graduations from 1 to 10 from left to right there are 10 secondary graduations between each of the main graduations there is a line that begins. at the left end of the ruler 10 secondary graduations to the left of the “1 main graduation the right end of the line ends on the eighth secondary graduation to the right of 3 how long is the line

Isopropyl alcohol, (ch3)2choh, is a common solvent. determine the percent by mass of hydrogen in isopropyl alcohol. a) 6.71% h b) 13.4% h c) 25.0% h d) 53.3% h