Answer: d. both (b) and (c)
Explanation:
Atoms are too small to be seen on microscopes, so we model them based on theories.
Answer;
56 kg of water
Solution;
Weight = 62 kg of water in 93 kg of a person
W=km
62=93k;
k=2/3
W=(2/3)84
=56 kg
Therefore; a 84-kg person will have 56 kg of water.
Answer:
Qsp > Ksp, BaCO3 will precipitate
Explanation:
The equation of the reaction is;
Na2CO3 + BaBr2 -------> 2NaBr + BaCO3
Since BaCO3 may form a precipitate we can determine the Qsp of the system.
Number of moles of Na2CO3 = 0.96g/106 g/mol = 9.1 * 10^-3 moles
concentration of NaCO3 = number of moles/volume of solution = 9.1 * 10^-3 moles/10 L = 9.1 * 10^-4 M
Number of moles of BaBr2 = 0.20g/297 g/mol = 6.7 * 10^-4 moles
concentration of BaBr2 = 6.7 * 10^-4 moles/10 L = 6.7 * 10^-5 M
Hence;
[Ba^2+] = 6.7 * 10^-5 M
[CO3^2-] = 9.1 * 10^-4 M
Qsp = [6.7 * 10^-5] [9.1 * 10^-4]
Qsp = 6.1 * 10^-8
But, Ksp for BaCO3 is 5.1*10^-9.
Since Qsp > Ksp, BaCO3 will precipitate
Yes, remember a chemical reaction is whenever one or more substances combine together to form a different substance. So whatever you put together and form something new is called a chemical change/reaction. Examples such as rusting of Iron, expired milk(going sour), Baking cake and many more to think about
Hope it helps
The number in isotope platinum-194 stands for the <em>total </em>amount of protons and neutrons. In other words, this is the mass. =)
