<span>Ca(NO3)2 + Na2CO3 = CaCO3 + 2NaNO3
Yes a precipitate of Calcium Carbonate is formed since it is insoluble in water.
Mol Wt of Calcium Nitrate is 164. And that of Calcium Carbonate is 100.
One mole of Calcium Nitrate produces one mole of Calcium Carbonate.
i.e. 164 gms will produce 100gms of precipitate
So, 1.74gms of Calcium Carbonate will be obtained from 2.85gms Calcium Nitrate present in the original solution.</span>
Answer:
Dmitry Mendeleev
Explanation:
Around 1869 a Russian scientist, Dmitry Mendeleev formed what is now known as the periodic table or chart. The Mendeleevian periodic table was based on the atomic weights of elements using the periodic law. The periodic law states that "chemical properties of elements are a periodic function of their atomic weights".
The modern periodic table was re-stated by Henry Moseley in the 1900s. He changed the basis of the periodic law to atomic masses.
7.32 moles of Chromium is present in 4.41 × 10²⁴ atoms.
<h3>How to find the number of moles ?</h3>
Number of moles = 
<h3>What is Avogadro's Number ?</h3>
Avogadro's number is the number of particles in one mole of substance. 6.022 × 10²³ is known as Avogadro's Constant / Avogadro's Number.
Avogadro's Number = 6.022 × 10²³
Now put the values in above formula we get
Number of moles = 
= 
= 7.32 moles
Thus from the above conclusion we can say that 7.32 moles of Chromium is present in 4.41 × 10²⁴ atoms.
Learn more about the Avogadro's Number here: brainly.com/question/1581342
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Answer:

Explanation:
We want to convert from moles to grams, so we must use the molar mass.
<h3>1. Molar Mass</h3>
The molar mass is the mass of 1 mole of a substance. It is the same as the atomic masses on the Periodic Table, but the units are grams per mole (g/mol) instead of atomic mass units (amu).
We are given the compound PI₃ or phosphorus triiodide. Look up the molar masses of the individual elements.
- Phosphorus (P): 30.973762 g/mol
- Iodine (I): 126.9045 g/mol
Note that there is a subscript of 3 after the I in the formula. This means there are 3 moles of iodine in 1 mole of the compound PI₃. We should multiply iodine's molar mass by 3, then add phosphorus's molar mass.
- I₃: 126.9045 * 3=380.7135 g/mol
- PI₃: 30.973762 + 380.7135 = 411.687262 g/mol
<h3>2. Convert Moles to Grams</h3>
Use the molar mass as a ratio.

We want to convert 3.14 moles to grams, so we multiply by that value.

The units of moles of PI₃ cancel.


<h3>3. Round</h3>
The original measurement of moles has 3 significant figures, so our answer must have the same. For the number we calculated, that is the tens place.
The 2 in the ones place tells us to leave the 9.

3.14 moles of phosphorous triiodide is approximately equal to <u>1290 grams of phosphorus triodide.</u>
A stable arrangement of eight valence electrons : ³⁵Cl⁻¹
<h3>Further explanation</h3>
Chlorine is a halogen gas, located in group 17, p block
Chlorine has an atomic number of 17 and an atomic mass of 35
Electron configuration: [Ne] 3s²3p⁵
If we look at the electron configuration, then Cl will bind 1 more electron so that the configuration is stable like Argon (atomic number 18)
So by binding this one electron, chlorine forms negative ions (anions)
³⁵Cl⁻¹
B. Cl⁻² binds 2 electrons, exceeding the octet rule
C. Cl⁺¹, releases 1 electron, remains unstable
D. Cl, the neutral form of Cl, is still unstable with a 7-electron valence configuration