When ammonium bicarbonate is heated, the white solid disappears, steam escapes the test tube and an odor of ammonia is detected. Is this a chemical change?

If the density of water is 1.0 g/cm3, which of these materials would float in water, based on their densities? check all that apply. aluminum cork iron lead wax

When hydrochloric acid reacts with potassium hydroxide solution, the following reaction occurs. hcl (aq) + koh (aq) h2o (l) + kcl (aq) the reaction gives off heat energy, so it is an reaction.

Which of these statements best explains why space exploration should be encouraged? it prepares humans to live without oxygen. it dispel myths about objects in space. it prevents comets and asteroids from striking earth. it creates technology to absorb harmful radiations in space.