Answer:
[MgCl₂] = 0.036 M
Explanation:
Molarity are the moles of solute in 1L of solution.
For this case, our solution's volume is 2L
First of all, we convert the mass of solute (MgCl₂) to moles
6.92 g . 1mol / 95.2 g = 0.0727 moles
Now, we make a rule of three:
In 2L of solution we have 0.0727 moles of solute
Then, in 1L of solution we may have, 1L . 0.0727 mol / 2L = 0.036 M
1) The nucleus of an atom loses 2 protons and 4 neutrons.
2) The nucleus of an atom gains a proton and it's neutrons remain the same.
Answer:
A- beryllium
B- calcium
C- magnesium
Explanation
NOTE: all element in group 2 have 2 balance electrons
First let’s start with B- number of electrons= number of protons which is equal to the atomic number. therefore, the answer is calcium as it’s atomic number is 20
C- magnesium will have three energy levels considering it has 12 electrons (2,8,2).
A- beryllium is the lightest one in group 2 as it has the atomic mass of 9.0122.
6.79 x 10⁶
<h3>Further explanation </h3>
Scientific Notation consists of 2 parts
1. the first part: the first digit followed by the decimal point
2. The second part: the power of 10 (the exponents).which shows the number of digits after the decimal point
To add/subtract, the exponents must be the same and then add/subtract the coefficient
- convert the largest exponent
- subtract the coefficients
Answer:
endothermic
Explanation:
Heat is added to make the process possible.
