An unknown substance undergoes a chemical change that gives off heat. What can you tell me about this substance?

Question 4 (higher question) Electrolysis of acidified water can produce hydrogen and oxygen. The apparatus for the electrolysis is: .

What is the experimental KHP concentration in a sample containing 10 mL of KHP solution (via volumetric pipet) that takes 12.39 mL of 0.04150 M NaOH to neutralize?

In the ground state, an atom of which element has two valence electrons

What is the percent of N in NH3?

The chemical reaction 2 H2O + energy → 2 H2 + O2 is 1. a synthesis reaction. 2. an endothermic reaction. 3. an exothermic reaction. 4. an ionic reaction.

Which of these is not a covalent molecule? 1. F2 2. CO 3. LiF 4. NH3

Define buffer capacity. a. buffer capacity is the amount of acid or base that can be added to a buffer without destroying its effectiveness. b. buffer capacity is the amount of acid that can be added until all of the base is used up. c.

Which of the following is not a chemical reaction a) gas formation b) solid formation c) energy change d) state change

How many moles of copper are needed to react with sulfur to produce 0.25 moles Ol copper (1) sulfide according to the following reaction: 2 Cu + S + Cuzs

If you wish to warm 52 kg of water by 22 ∘c for your bath, find what the quantity of heat is needed. express your answer in calories cal.