Robert Hooke deterred that all animals were made of cells
Answer:
NaCl consists of one atom each of sodium and chlorine. Hence, each molecule of NaCl has 2 atoms total.
Explanation:
IT will be easy to know how chemical reactions occur
It will helps to know the fundamental particles of an atom
Answer:
A. there is an isotope of lanthanum with an atomic mass of 138.9
Explanation:
By knowing the different atomic masses of both Lanthanum atoms, we can not tell anything about their occurence in nature. Therefore, all the last three options are incorrect. Because, the atomic mass does not tell anything about the availability or natural abundance of an element.
Now, the isotopes of an element are those elements, which have same number of electrons and protons as the original element, but different number of neutrons. Therefore, they have same atomic number but, different atomic weight or atomic masses.
Hence, by looking at an elements having same atomic number, but different atomic masses, we can identify them as isotopes.
Thus, the correct option is:
<u>A. there is an isotope of lanthanum with an atomic mass of 138.9.</u>
The average kinetic energy of 1 mole of a gas at -32 degrees Celsius is:
3.80 x 103 J
The relationship between volume and temperature of a gas, when pressure and moles of a gas are held constant, is: V*T = k.
FALSE
The relationship between moles and volume, when pressure and temperature of a gas are held constant, is: V/n = k. We could say then, that:
If the moles of gas are tripled, the volume must also triple.
If the temperature and volume of a gas are held constant, an increase in pressure would most likely be caused by an increase in the number of moles of gas.
TRUE
If the vapor pressure of a liquid is less than the atmospheric pressure, the liquid will not boil.
TRUE
35 - AB
36 - BD
33 - true
34 - False
20 - 6
21 - orthohombic
