If an element has 13 protons, how many electrons are in its outer shell?

Sodium has 1 valence electron, which it shares with fluorine to form a covalent bond. a. True b. False

Which statement is false? a Changes occur quicker in secondary succession because soil is already present. b The end result is a climax community in both primary and secondary succession. c There is always soil present when primary succession starts.

50cm3 of sodium hydroxide solution was titrated against a solution of sulfuric acid. The concentration of the sodium hydroxide solution was 20g/dm3.

What is the pH of a solution obtained by dissolving two extra-strength aspirin tablets, containing 470 mg of acetylsalicylic acid each, in 240 mL of water?

24 Which compound is classified as a hydrocarbon? (1) butanal (3) 2-butanol (2) butyne (4) 2-butanone

Paint, paint thinners and some cleaning agents can weaken the shell of a hard hat and may eliminate

A 10 chunk of metal has a specific heat of 0.25 J/g ºC. The temperature is changed from 10ºC to 45ºC. How much heat is required?

In this reaction what is the correct coefficient for sodium chloride? pb (no3) 2? nacl → pbcl2? nano3

Classify each of the following as a path function or a state function. work energy distance traveled enthalpy heat

Flammable materials like alcohol should never be dispensed or used near True or False