How properties before and after a chemical reaction can be used to determine if a chemical reaction occurred

What is the difference between 5.0g and 5.00g?

The Lewis structure for carbon hydrogen cyanide (HCN) is given. What is the three-dimensional shape of the molecule? A. Bent B. Linear C. Tetrahedral D. Trigonal planar

The state of matter a substance is in depends on what?

Which of the following is a testable hypothesis? A) The Harry Potter books are better than the Nancy Drew books. B) More 10-year-olds prefer riding bikes to playing video games, but more 13-year-olds prefer video games.

Which of the following will increase the salt concentration in seawater? evaporation runoff precipitation ice cap melting

How do scientist know that atoms and molecules combine in well-ordered arrays?

Explain why potassium and argon react together

Which indicator will be the same color in hydrochloric acid as it is in pure water? 1. methyl orange 2. phenolphthalein 3. bromcresol green

Based on your knowledge of energy resources conservation, which of the following statements is true? a) Manufacturers can increase a light bulb's energy efficiency by using technology that decreases the amount of electromagnetic energy the bulb

Ammonia (nh3 (g), hf = - 46.19 kj/mol) reacts with hydrogen chloride (hcl (g), hf = - 92.30 kj/mol) to form ammonium chloride (nh4cl (s), hf = - 314.4 kj/mol) according to this equation: