Answer:
1s2 2s2 2p6
Explanation:
The nitride ion(N^3-) is formed when nitrogen gains three electrons. Nitrogen possesses seven electrons in its orbitals and ordinarily has the electronic configuration; 1s2 2s2 2p3. However,being in group 15, nitrogen can accept three electrons to form the nitride ion and complete its octet of electrons. When this happens, three electrons are added to the nitrogen atom and the electronic configuration is now the same as that of Neon, its closest noble gas which is 1s2 2s2 2p6. Hence the answer given above.
Elements can accept or donate electrons in order to complete their octet structure in accordance to the octet rule which states that atoms and ions must possess eight electrons in their outermost shell in order to attain chemical stability. The reason for ion formation and chemical reaction is in order for species to attain the octet structure.
Ice melts when heat energy causes the molecules to move faster, breaking the hydrogen bonds between molecules to form liquid water.
Weathering of the rock and sedimentation are decomposition processes. Through time, the minerals in the rocks soften due to pressure and heat. So, they crumble down and reduce in terms of size. Once they do, they become sand or part of the soil. So, the answer is A.
Henlo!
Bohr's model was unable to calculate or it required precise information about position of an electron and its velocity. It is very difficult to calculate velocity and position of an electron at the same time because electron i too small to see and may only be observed if peturbed, for example we could hit the electron with another particle such as photon or an electron, or we could apply electric or magnetic field to the electron. This will inevitably change the position of the elctron or its velocity and direction. Heisenberg aid that more precisely we can define the position of an electron, the less certainity we are able to define its velocity and vice versa.
In short, first option is correct one

☃️ 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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