During the action of a sodium-potassium pump, 50 ATP molecules were spent. Predict how many sodium ions are transported across the cell membrane.

How do we know that caramelizing sugar is a chemical change?

What are different ways to separate praticles and grains?

Which one of the following neutral salt? A. CaCO3 B. NaHSO4 C. Zn (OH) Cl D. NH4OH

The ph of lemon juice is approximately 2.4. at this ph, the hydronium ion concentration is closest to which value? 1. 250 m 2. 4.00 * 10-3 m 3. 2.50 * 10-12 m 4. 5.62 * 10-4 m

An open-end manometer containing mercury was connected to a vessel holding a gas at a pressure of 767 torr. The atmospheric pressure was 724 torr. What is the difference in the heights of the mercury, expressed in cm?

What is most believed by most scientists about the age of our solar system.

The water level in a graduated cylinder stands at 20.0 ml before and at 26.2 ml after a 16.74 g metal sample is lowered into the cylinder. what is the density of the sample. what metal is the sample most likely to be

An electrolyte is a substance that will conduct electricity when dissolved in water. a substance that conducts electricity well is a strong electrolyte. a substance that conducts electricity poorly is a weak electrolyte.

Energy is required to produce a chemical change during (1) chromatography (2) electrolysis (3) boiling (4) melting

What is the definition of colorie