Answer: 3.72 M
Explanation:
Expression for rate law for first order kinetics is given by:

where,
k = rate constant = 
t = age of sample = 15.0 minutes
a = let initial amount of the reactant = 10.0 M
a - x = amount left after decay process = ?




The concentration of
in a solution after 15.0 minutes have passed is 3.72 M
Answer:
The answer would be It breaks them up.
Explanation:
Polar covalent bond- a bond where atoms are unevenly shared due to a larger difference in electronegativity of the bonded elements.
Non-polar covalent bond- These are bonds between elements with a low difference in electronegativity. Electrons are shared equally in these bonds between the elements.
Ionic bonds- have such large difference in electronegativity that they take/give electrons to the element they are bonded to. They do not share electrons at all. Bonds between a non-metal and a metal.
Elements have neutral charges such as Na so if X has 72 protons + charges then it must also have 72 electrons with - charges
hope that helps
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