Is biting an apple a physical or chemical change?

Darwin's theorized that three conditions were necessary for natural selection to occur, which of the following is NOT one of them? stable environment struggle for existence variation inheritance

Which of the following occurs in this system? A. Water does not cross the membrane at all. Water flows equally in both directions. B. There is a net flow of water from the 10% starch solution into the 4% starch solution. C.

If only 1/2 the energy necessary to go between the 1s and 2s level was available, will an electron go to the 2s?

How many moles of butane gas, C4H10, react to produce 2.50 moles of H2O? How many moles of oxygen gas reacts? Given the balanced equation is, 2C4H10+13O2 = 8CO2+10H2O

a sample of seawater has a pH of 8. determine the new pH of the sample if the hydrogen ion concentration is increased by a factor of 100

A sample of methane gas occupies 4.50 gallons at a temperature of 80.0 F. If the pressure is held constant, what will be the volume of the gas at 100. degrees C?

Jack wants to know if it takes longer for warm water to freeze into ice cubes than cold water, so he performed the following experiment. Jack placed 50 mL of water in the refrigerator and allowed it to cool to a temperature of 4°C.

How to calculate average concentration

Suppose that you measure a pen to be 10.5 cm long. Convert this to meters.

How are amounts of hydrogen and oxygen gas made from the electrolytic decomposition of water related to the chemical formula of water?