Answer:
Mass = 8.5 g
Explanation:
Given data:
Mass of ammonia = ?
Number of moles = 0.5 mol
Solution:
Formula:
Mass = number of moles × molar mass
Molar mass of ammonia = 17 g/mol
By putting values,
Mass = 0.5 mol × 17 g/mol
Mass = 8.5 g

☃️ Chemical formulae ➝ 
<h3>
<u>How to find?</u></h3>
For solving this question, We need to know how to find moles of solution or any substance if a certain weight is given.

<h3>
<u>Solution:</u></h3>
Atomic weight of elements:
Ca = 40
C = 12
O = 16
❍ Molecular weight of 
= 40 + 12 + 3 × 16
= 52 + 48
= 100 g/mol
❍ Given weight: 10 g
Then, no. of moles,
⇛ No. of moles = 10 g / 100 g mol‐¹
⇛ No. of moles = 0.1 moles
☄ No. of moles of Calcium carbonate in that substance = <u>0.1 moles</u>
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"The boron-nitrogen interaction in the studied molecules shows some similarities with the N→B bond in the H3N-BH3 molecule, formally understood as covalent-dative. ... The results show that all the studied BN bonds are triple, since three two-center orbitals have been obtained."
"Formation of a dative bond or coordinate bond between ammonia and boron trifluoride. When the nitrogen donates a pair of electrons to share with the boron, the boron gains an octet. ... In addition, a pair of non-bonding electrons becomes bonding; they are delocalized over two atoms and become lower in energy."
In chemical changes molecules in the reactants interact to form new substances, which mean means are broken up to form new bonds. No atoms are created or destroyed while undergoing the chemical change. In a physical change more like a state of change meaning shape, size or anything that effects how the object looked before then no new substances are formed.