Answer:The 2nd and 3rd one.
Explanation:
It has the same number of protons but different amount of nuetrons.
Explanation:
Beryllium is a group 2 element and its atomic number is 4. Electronic configuration of beryllium is 
.
Since, a beryllium contains two valence electrons so, in order to attain stability it will readily lose its 2 valence electrons.
Therefore, a beryllium atom upon losing two valence electrons will acquire a +2 charge.
Thus, we can conclude that the net ion charge of Beryllium is +2.
Answer:
A) 4.3 × 10²⁴ atoms
Explanation:
Step 1: Given data
Moles of neon: 7.2 moles
Step 2: Calculate the number of atoms present in 7.2 moles of neon
In order to convert moles to toms, we need a conversion factor. In this case, we will use Avogadro's number: there are 6.02 × 10²³ neon atoms in 1 mole of neon atoms.
7.2 mol × 6.02 × 10²³ atoms/mol = 4.3 × 10²⁴ atoms
Your answer is 1-3-2-4 , grass sand water rock
Answer:
2.12×10²³ atoms.
Explanation:
From Avogadro's hypothesis, we understood that 1 mole of any substance contains 6.02×10²³ atoms. This simply means that 1 mole of zirconium also 6.02×10²³ atoms.
Thus, we can obtain the number of atoms present in 0.3521 mole of zirconium as follow:
1 mole of zirconium also 6.02×10²³ atoms.
Therefore, 0.3521 mole of zirconium will contain = 0.3521 × 6.02×10²³ = 2.12×10²³ atoms.
Therefore, 0.3521 mole of zirconium contains 2.12×10²³ atoms.
