Answer:
7.5 g
Explanation:
There is some info missing. I think this is the original question.
<em>Ammonium phosphate ((NH₄)₃PO₄) is an important ingredient in many fertilizers. It can be made by reacting phosphoric acid (H₃PO₄) with ammonia (NH₃). What mass of ammonium phosphate is produced by the reaction of 4.9 g of phosphoric acid? Be sure your answer has the correct number of significant digits.</em>
<em />
Step 1: Write the balanced equation
H₃PO₄ + 3 NH₃ ⇒ (NH₄)₃PO₄
Step 2: Calculate the moles corresponding to 4.9 g of phosphoric acid
The molar mass of phosphoric acid is 98.00 g/mol.

Step 3: Calculate the moles of ammonium phosphate produced from 0.050 moles of phosphoric acid
The molar ratio of H₃PO₄ to (NH₄)₃PO₄ is 1:1. The moles of (NH₄)₃PO₄ produced are 1/1 × 0.050 mol = 0.050 mol.
Step 4: Calculate the mass corresponding to 0.050 moles of ammonium phosphate
The molar mass of ammonium phosphate is 149.09 g/mol.

Answer: Polythene
Polythene is a synthetic polymer classified as plastics.
Explanation:
Polythene is formed artificially from several repeating units of ethene molecules (monomers) in a reaction known as polymerization.
The polyethene can be represented as [CH2-CH2]n, where n is thousands to ten thousands unit of ethene.
It is used to make
- plastic bags,
- cable insulators
- plastic crates etc
Thus, polythene is a synthetic polymer of ethene, and classified as plastics.
Answer:

Explanation:
Given,
The density of Helium is 
We need to find the density in Dg/μm
We know that,
1 g = 10 dg
1 cm³ = 10¹² μm³
So,

So, the density of Helium is equal to
.
Answer:
2.13 g
Explanation:
(142.04)(0.0150) = 2.13 g
Answer:
Li⁺
Explanation:
Li⁺ ions has a noble gas electron configuration because it resembles that of He.
To have a noble configuration, electrons in the outermost shell must completely fill their respective orbitals.
Li⁺ is an ion that has lost one electron from the usual number of 3 thereby remaining 2 electrons.
The electronic configuration is given as;
Li⁺ 1s²
The S orbital can hold a maximum number of just two electrons.
Helium atom has two electrons with electronic configuration of 1s²
Therefore Li⁺ = 1s² = He