Answer: if you examine the rock u might see that it has been in lava before or is dark from burns
Explanation: i dont know if im right but pls mark brainliest
There are two naturally occurring isotopes of gallium: mass of Ga-69 isotope is 68.9256 amu and its percentage abundance is 60.11%, let the mass of other isotope that is Ga-71 be X, the percentage abundance can be calculated as:
%Ga-71=100-60.11=39.89%
Atomic mass of an element is calculated by taking sum of atomic masses of its isotopes multiplied by their percentage abundance.
Thus, in this case:
Atomic mass= m(Ga-69)×%(Ga-69)+X×%(Ga-71)
From the periodic table, atomic mass of Ga is 69.723 amu.
Putting the values,

Thus,

Rearranging,

Therefore, mass of Ga-71 isotope is 70.9246 amu.
B. 1, 1, 1, 2
Explanation:
You only need to balance the NaNO3 on the right. Since there is 2 NO3 on the left, you need to put a 2 in front of the NaNO3 on the right. Everything else is already balanced so the only coefficient needed is 2 in front of the NaNO3.
Answer:
Explanation:
A chemical property describes the ability of a substance to undergo a specific chemical change.
A chemical reaction is a process that occurs when one or more substances are changed into one or more new substances.
Differences
Chemical properties are properties that can be observed or measured when a substance undergoes a chemical change.
Physical properties are properties that can be observed without bringing a chemical change.
Another one
chemical properties; can be used to predict how substances react.
chemical changes; It is mostly used in identifying or describing the substance.
1) Radioactive decay is the spontaneous decomposition of the unstable nucleus of an atom.
2) The emission of a particle or a photon.
For example, alpha decay is radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus).
3) The result is usually more stable element with smaller atomic number.
For example, in alpha decay atom transforms into an atom with an atomic number that is reduced by two and mass number that is reduced by four.
For example nuclear fission is radioactive decay process in which the nucleus of an atom splits into smaller parts and huge amount of energy is released.