Which reaction is exothermic?

CH4 + 2O2 - - >CO2 + 2H2O + 891 kJ

NH4NO3 + H2O + 25 kJ - - > NH4 + (aq) + NO3 - (aq)

2H2O + 286 kJ - - > 2H2 + O2

N2 + O2 + 181 kJ-->2NO

If I have 251.14 grams of citric acid and calcium bicarbonate mixture how much citrus acid do I have?

Which metalloid has 3 electrons in its 5p orbitals

How many moles of O2 are needed to completely react with 9.5 grams of Na?

Is berkelium flammable

Define and describe each of the following forms of energy and then classify each as either: potential energy, kinetic energy, or a transfer of some quantity of energy.

Which of the following statements describes how the periodic table is organized? 1. The elements are organized alphabetically. 2. The elements are organized by their size. 3. The elements are organized by the date they were discovered. 4.

Which of the following is a mixture A aluminum B BaSO3 C Milk D table salt

Which of the following quantum number combinations is not allowed in an atom? A. n = 2, l = 1, mr = - 1 B. n = 1, l = 1, m = 0 C. n = 8, l = 5, m = - 4 D. n = 6, l = 3, m = 2

13. Adding thermal energy to a gas at constant pressure will cause

A 3 ml volume of a solution containing an unknown concentration of hcl is added to 7 ml of water. it is then determined that the concentration of the hcl in the diluted solution is 630 mm. what was the concentration of hcl in the original solution?