Isotopes are atoms of the same element that differ in the number of neutrons.
Remember that all the atoms of an element have the same number of protons. So the only difference between isotopes of an element is the number of neutrons.
86 Sr means that the mass number of this isotope is 86. Also, remember that the mass number is the number of protons plus the number of neutrons.
87 Sr means that the mass number of this isotope is 87.
So, 86 Sr and 87 Sr differ 1 neutron.
Answer: 1 neutron
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The reactant in a chemical reaction that limits the amount of product that can be formed. The reaction will stop when all of the limiting reactant is consumed
The vapor pressure (in torr) of a 35°C solution : 52 torr
<h3>Further explanation</h3>
Given
x propanol = 0.75
P°ethanol=100 torr
P°propanol=36 torr
Required
the vapor pressure
Solution
Raoult's Law
P solution = xA.P°A +xB.P°B
x ethanol = 1- 0.75 = 0.25
Input the value :
P solution = 0.25 x 100 + 0.75 x 36
P solution = 25 + 27
P solution = 52 torr
Answer:
Covalent bonds
Explanation:
There are about three kinds of bonds in chemistry;
Ionic bonds
Covalent bonds
Metallic bonds
Substances that possess ionic and metallic bonds all have high melting and boiling points.
However, covalent molecules often have low melting and boiling points due to weak intermolecular forces in the solid state. They also have a dull appearance and do not dissolve in water.
