Which of the following is not an example of a chemical change?

Digesting food

Burning gas in an engine

Cooking eggs

Grinding pepper

What was discovered first helium or samarium?

In an ion, the sum of the oxidation states is equal to the overall ionic charge. Note that the sign of the oxidation states and the number of atoms associated with each oxidation state must be considered.

How many grams are in 6.8 moles of C6H1206

An equimolar mixture of N2 (g) and Ar (g) is kept inside a rigid container at a constant temperature of 300 K. The initial partial pressure of Ar in the mixture is 0.75atm.

If you pass electricity through pure water so that it changes to hydrogen and oxygen gas, what type of reaction has taken place? A. Synthesis B. Decomposition C. Single displacement D. Double displacement

What water activities might be easier to do in Lake Assal's salty water? What activities could be more difficult?

The suffix "-megaly in the term gastromegaly means:

The harder you strike a drum, the greater the sound's A) medium B) volume C) frequency D) pitch

The equation X + Y 2Z has the rate law equation shown below. Which of the following statements best describes the relationship of X on the rate of the reaction? rate = k[X]2[Y] Changing X has no effect on the reaction rate.

What moves in or out of a substance during a change of state?