Answer:
272.31× 10²³ atom of strontium
Explanation:
Given data:
Number of moles of strontium = 45.22 mol
Number of atoms = ?
Solution:
The given problem will solve by using 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.
1 mole = 6.022 × 10²³ atoms
45.22 mol × 6.022 × 10²³ atom / 1 mol
272.31× 10²³ atom
37.8 g CH2Br2 X (1 mol CH2Br2 / 173.83 g) = 4.60X10^-3 mol CH2Br2
<span>4.60X10^-3 mol CH2Br2 X (2 mol Br / 1 mol CH2Br2) X 6.02X10^23 atoms/mol = 5.54X10^21 bromine atoms</span>
Answer:
144cm²
Explanation:
Given dimensions:
Length x breadth x thickness
18cm x 8cm x 5cm
The widest part of this figure will be the face containing the length and the breadth.
The breadth is the width of the figure;
Area of the widest part = length x breadth = 18cm x 8cm = 144cm
The area of the widest part of the figure is 144cm²
The ch4 molecule exhibits hydrogen bonding.
This statement is false. A CH4 molecule do not have a hydrogen bonding instead it has dipole dipole attraction.
Hydrogen bonding occurs when a hydrogen atom is covalently bonded to an N, O, or F atom.
This would be a true statement. A hydrogen bond is present when an atom of hydrogen shares electrons with O, N or F atom.
A hydrogen bond is equivalent to a covalent bond.
This is a false statement. A hydrogen bond is an intermolecular force of attraction while covalent bond is a intramolecular force. So, they would mean different things.
a hydrogen bond is possible with only certain hydrogen-containing compounds.
This would be true. Without the presence of an hydrogen atom definitely there would be no hydrogen bond.
a hydrogen atom acquires a partial positive charge when it is covalently bonded to an f atom.
This would be true since a HF is a polar molecule.
Conditions for rusting
• moisture
•oxygen
Prevention
•Painting
• Galvanisation
• Making Alloys
• greasing
Hope this helps you ;)(:
