Which of ther following is the best example of a closed system?

How many atoms of each element are present in the nucleotide adenine:C9H14N3O8P

Solution 1 contains 3.5g of sodium chloride in 500 mL of water. Solution 2 contains 7.5g of glucose in 300 mL of water.

Two beakers contain clear. colorless liquids. When the contents of the beakers are mixed a white solid is formed, (a) Is this an example of a chemical or a physical change?

How many moles of air are there in a human lung with a volume of 2.4 L at STP? Explain your answer

Which of the following statements is true about calorimetry? Heat released by the system is equal to heat released by the surroundings. Heat absorbed by the system is equal to heat absorbed by the surroundings.

Read the following passage: The movement of tectonic plates buries a rock deep inside Earth. Intense heat and pressure change the mineral composition of the rock and transform it into Rock A.

What is a change which forms one or more new substances?

Which changes occur as a cadmium atom, Cd, becomes a cadmium ion, Cd2+? (1) The Cd atom gains two electrons and its radius decreases. (2) The Cd atom gains two electrons and its radius increases.

Explain Charles law

2 H2 + O2 → 2 H2O What is the product of this chemical reaction