Which change is exothermic?

(1) freezing of water (2) melting of iron (3) vaporization of ethanol (4) sublimation of iodine

The most difficult kind of frustration a person must deal with is probably A. financial frustration. B. getting a poor grade after working hard on school project. C. not being appreciated on the job. D.

Which type of bond would most likely be found in HBr

Which example best describes a double displacement reaction? The ions of two ionic compounds switch places and a gas is formed. A compound reacts with oxygen to release a lot of heat. One compound breaks down into two different compounds.

Consider the elements bromine and chlorine; which element has a larger ionic radius? -chlorine -bromine

Students of different ages were given the same jigsaw puzzle to put together. They were timed to see how long it took to finish the puzzle. Which on is the Independent variable, dependent variable, and controlling variables?

A scientist in London and a scientist in California both conducted independent investigations that produced similar results.

When magnesium combines with oxygen, the reaction involves a. a conversion of protons into electrons. b. sharing of electrons between Mg and O. c. transfer of electrons from Mg to O. d. transfer of electrons from O to Mg.

The activation energy for the reaction no2 (g) + co (g) ⟶no (g) + co2 (g) is ea = 100 kj/mol and the change in enthalpy for the reaction is δh = - 375 kj/mol.

What process transform solar energy into chemical energy?

When the reaction was carried out the calculated theoretical yield for water was 176 grams but the measured yield was 148 grams what is the percent yield