The answer is B because isotopes have the same number of protons and neutrons.
Answer:
Electrons orbit the nucleus.
Answer:
Exothermic reactions feel hot
Endothermic reactions feel cool
Explanation:
In an exothermic reaction, heat is given out by the system. The energy of the reactants is greater than that of the products hence the excess energy is given off as heat. The reaction vessel feels hot.
In an endothermic reaction, the energy of products is greater than that of the reactants hence energy is taken into the system and the reaction vessel feels cool.
<span>0.38
You first calculate the total moles by dividing the grams by molecular weight:
45 g N2 / 28.02 g/mol = 1.6 mol N2
40 g Ar / 39.95 g/mol = 1.0 mol
Then you divide the moles of Ar by the total number of moles:
1.0 / (1.6 + 1.0) = 0.38 mol fraction</span>