Which of the following represents a hydrogen displacement reaction? Group of answer choices 2Al(s) + 3H 2SO 4(aq) → Al 2(SO 4) 3(aq) + 3H 2(g) 2C 2H 6(g) + 7O 2(g) → 4CO 2(g) + 6H 2O(l) 2KBr(aq) + Cl2(g) → 2KCl(aq) + Br2(l) CaBr2(aq) + H2SO4(aq) → CaSO4(s) + 2HBr(g) N 2(g) + 3H 2(g) → 2NH 3(g)

Why should the scientific method be used to answer a question? a. it provides a way to test an idea without any bias. b. it provides a way to test a hypothesis. c. it provides a way to ensure all hypotheses are proven correct. d. it provides a way to quickly turn a hypothesis into a scientific theory.

Summarize possible ways in which phases of matter could combine to form a solution.

Sally is making a model of a magnesium atom with an atomic mass number of 24 for her chemistry class. she has foam balls for the protons, neutrons, and electrons. she has added 6 neutrons to her model so far. how many more neutrons does she need to add to complete her neutral atom of magnesium?