Answer:
to show how substances in a chemical reaction interact
to shorten the explanation of a chemical reaction
to help keep track of atoms in a chemical reaction
Explanation:
Answer: NO2, CO, NH3 , Ne, He
Explanation : speed is inversely proportional to mass, also
Lightest particle has greatest average speed
A. Light reflected from the object's surface must enter your eyes.
Answer: -
2 x 10 ²⁴ atoms of Ag rounded off to 1 significant figures.
Explanation: -
Mass of Cu = 100 g
Molar mass of Cu = 63.55 g / mol
Number of moles of Cu = 100 g / (63.55 g/mol)
= 1.574 mol of Cu
The balanced chemical equation for the reaction is
Cu + 2AgNO₃ → Cu(NO₃)₂ + 2 Ag
From the balanced chemical equation we see
1 mol of Cu gives 2 moles of Ag
1.574 mol of Cu gives
= 3.148 mol of Ag
1 mole of Ag has 6.02 x 10 ²³ atoms of Ag according to Avogadro's Law.
3.148 mol of Ag has
= 18.95 x 10²³ atoms of Ag
= 2 x 10 ²⁴ atoms of Ag rounded off to 1 significant figures.
Answer:
Chemical reactions often involve changes in energy due to the breaking and formation of bonds. Reactions in which energy is released are exothermic reactions, while those that take in heat energy are endothermic.
Explanation: