How many atoms are in a sample of 72.8 grams calcium?

A bowling ball of 35.2kg, generates 218 kg. M/s units of momentum. What is the velocity of the bowling ball?

How is this an improvement on the traditional, paper coffee filters? A: they are less wasteful and more cost effective because they last longer B: a permanent filter is more expensive than a traditional filter C: they contain plastic which does not

In the reaction CaCO3 → CaO + CO2 100 grams of calcium carbonate (CaCO3) is observed to decompose upon heating into 56 grams of calcium oxide (CaO) and 44 grams of carbon dioxide (CO2). This is an illustration of

Could someone describe a procedure to separate a mixture of salt, sand, and water? Would a filter work to separate the sand and salt or just the sand? How would i separate the water and salt if it is dissolved in the water?

What element has one electron in its 4f sublevel?

If the pH indicator bromothymol blue was added to the nitric acid solution, it's colour would be?

Which statement describes a chemical reaction? Atoms in the products are rearranged to form new substances. Atoms in the reactants are rearranged to form new substances. Atoms in the products change into new atoms to form new substances.

The gases CO₂ (g) and NH₃ (g) can be liquefied at 20°C by compressing them to sufficiently high pressures. A student claims that NH₃ (g) can be liquefied at a lower pressure than CO₂ (g) can be liquefied.

Which is a pure substance A) mixture B) solution C) element

Samuel adds a teaspoon of salt to a glass of water. He notices that the song disappears. Samuel takes a sip to discover that the water taste salty. What kind of change has occurred?