<span>Fluoride is the element that is added to city water supplies and toothpastes to prevent tooth decay. According to research, fluoride helps to prevent tooth decay as it can reduce cavities by 24% and by boosting the production of saliva. Saliva helps to protect the tooth enamel by providing high levels of calcium and phosphate ions to the surface of the tooth.</span>
Answer:
Solids
Explanation:
At standard room temperature and pressure, most of the elements are solids.
Just a few of the elements are liquids and gases at this temperature.
The periodic table is made up of metals, metalloids and non-metals. Most of these substances are actually solid.
Some non-metals are gaseous at standard room temperature.
Answer:
Endothermic
Explanation:
This would be an endothermic reaction, due to the fact that the water would be signifigantly warmer then the ice cube, which causes it to melt.
Is constant (matter that has a composition that is the same everywhere)