As a group, living things must be able to do all of the following except A. respond to their environment. B. obtain and use energy. C. grow and develop. D. remain without change over time.

Determine the pH of 0.10 M NH3 solution. NH3 is a weak base with a Kb equal to 1.8x10-5 (round to the nearest whole number)

A gas is held at a constant pressure while its volume decreases from 450 mL to 200 mL. What will the final temperature be if the initial temperature is 25.0 degrees celsius? (Express temperature in K)

A phase diagram shows phase changes of a substance by illustrating which of the following? A. pressure vs. time B. pressure vs. density C. temperature vs. time D. pressure vs. temperature

Be sure to answer all parts. Calculate the pH during the titration of 30.00 mL of 0.1000 M KOH with 0.1000 M HBr solution after the following additions of acid: (a) 9.00 mL pH = 12.73 (b) 29.80 mL pH = 1 (c) 38.00 mL pH = 1.9

Hydrogen H 2. helium Mg 3. sodium K 4. magnesium He 5. potassium Na

Why is Earth's temperature just right for life? A. Earth's core is hot enough to heat Earth's surface. B. Earth's magnetic field creates suitable temperatures on Earth's surface. C. Earth's crust is warmed by heat from the sun. D.

Which of the following is an example of a chernical change? Boiling water Burning paper Dissolving sugar in water Melting gold

Part a by drawing molecular orbital diagrams for b2, c2, n2, o2, and f2, predict which of these homonuclear diatomic molecules are magnetic.

A student states that non-metal atoms share their core electrons when they form covalent bonds. What is wrong with this statement? A. Atoms do not share electrons during covalent bonding. B.

Boron has an average mass of 10.81. One isotope of boron has a mass of 10.012938 and a relative abundance of 19.80 percent. The other isotope has a relative abundance of 80.20 percent. What is the mass of the two isotopes?