What does the symbol ∆H stand for? the specific heat of a substance the heat capacity of a substance the heat of reaction for a chemical reaction one Calorie given off by a reaction

Iridium has two isotopes, 191Ir and 193Ir. If 193Ir is found in abundance of 62%, estimate which mass number the average atomic mass will be closest to.

How can it be deduced that metallic zinc and metallic lead displace hydrogen from strong acid, whereas metallic copper and silver do not?

What is the magnitude of total charge of all the electrons in 2.4 l of liquid water?

2. Using Charles's Law solve the following: A sample of helium has a volume of 125 L at a temperature of 127  C, if the volume is decreased to 85.0 L what is the resulting temperature considering pressure does not change.

What does ozone in the stratosphere above the earth consist of?

Convert 4.5 hours to seconds

Gasoline catches on fire is it flammability?

Enzymes are proteins that speed up chemical reactions in the body how do they work A. they increase the surface area of reactants B. they increase the concentration of reactants C. they decrease the concentration of products D. They act as reactants

Atomic number for bromine

A reaction with ΔH = - 13 kJ/mol and ΔS = - 22 J/K·mol, at 2°C, the reaction is: A) spontaneous B) nonspontaneous C) at equilibrium D) impossible to determine reactivity E) none of the above