Answer:
The molarity of acid is 3 M.
Explanation:
Given data:
Volume of H₃PO₄ = 25 mL
Volume of NaOH = 50 mL
Molarity of NaOH = 1.50 M
Molarity of H₃PO₄ = ?
Solution:
Formula:
M₁V₁ = M₂V₂
M₁ = M₂V₂ / V₁
M₁ = 1.50 M ×50 mL / 25 mL
M₁ = 75 M. mL / 25 mL
M₁ = 3 M
The molarity of acid is 3 M.
Answer:
$182 is the value of the gold in the coin
Explanation:
Diameter is 2r, the ratio of the coin is = 1.62cm / 2 = 0.81cm
Following the formula of the volume of the coin:
V = π r² h
V = π*(0.81cm)²*0.085cm
V = 0.172cm³ = mL
As the density of the gold is 19.32g/mL, the mass of 0.1752mL of gold is:
0.1752mL * (19.32g / mL) =
3.385g is the mass of the coin
As the price of the gold is $53.90 / g, the value of the gold in the coin is:
3.385g * ($53.90 / g) =
<h3>$182 is the value of the gold in the coin</h3>
Answer:
T2=540K or 267°c
Explanation:
- NZ 278°c, 0.625 atm P1/T1=P2/T2
- (27-->273=300K)
- T=?, 1.125 atm
- 0.625/300=1.125/T2
-
≠T2=
(divided both sides by 0.625)
Ans: T2=540K or 267°c How to get 267°c just subtract 540 from 273
Answer:
Option C = three electrons are gained, making N⁻³
Explanation:
Nitrogen is present in group 5A.
Its atomic number is seven.
It have five valance electrons.
Its electronic configuration is N₇ = [He] 2s² 2p³
In order to complete the valance shell or 2p subshell nitrogen must gain three more electrons.
When an atom gain the electrons anions are formed and negative charge is created on it.
When an atom lose its valance electrons cation is formed and positive charge is created.
That's why when nitrogen gain three electrons to complete the valance shell N⁻³ is formed.
Answer:
Explanation:
Substance are consist of very large number of atoms, ions , molecules etc.
They can not be count in a simple way. Scientist used Avogadro number to express the large number of atoms, ions, molecules.
Avogadro number:
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
96.06 g of SO₄²⁻ ion = 1 mole of SO₄²⁻ ion = 6.022 × 10²³ ions of SO₄²⁻
