Ascientist is studying a previously unknown chemical reaction. she concludes that it is exothermic. what must the scientist have observed?
the reaction released heat.
the reaction formed a gas.
the reaction sped up when a catalyst was added.
the reaction caused the container to get cold.

The valence of aluminum is +3, and the valence of the chlorine is -1. the formula fir the aluminum chloride is correctly written as

Element before carbon on the periodic table

Read the claim. breakfast is an important meal. it jump starts the body’s process of using calories to break down food. appetite can decrease with age, but going too long without eating causes metabolism to slow down. current research shows that incorporating legumes such as lentils and chickpeas into meals boosts metabolism for twenty-four hours. who might benefit from this claim? people who have a fast metabolism stores that sell exercise equipment people who take vitamin supplements grocery stores that sell legumes