What is true of a physical change? 1) results in a rearrangement of the elements that make up the substance 2) results in a substance that is still the same substance 3) results in a substance with completely different physical properties 4) results in a new substance that is not the same substance

1. combine iron and copper (ii) sulfate solution. (hint: iron will form the iron (iii) ion) fe + cuso4 → 2. combine lead (ii) nitrate and potassium iodide solutions. pb(no3)2+ kl → 3. combine magnesium metal and hydrochloric acid solution. mg + hcl → 4. electrolysis (splitting) of water. h2o → 5. burning magnesium. mg + o2 →

8.98 dm3 of hydrogen gas is collected at 38.8 °c. find the volume the gas will occupy at -39.9 °c if the pressure remains constant.

Which of the following words describe the reality that the universe looks the same from various perspective