Explanation:
<u>Moles is denoted by given mass divided by the molecular mass , </u>
Hence ,
n = w / m
n = moles ,
w = given mass ,
m = molecular mass .
For example ,
For a compound X ,
The given mass i.e. w = 20 g
and the molecular mass ,i.e. , m = 10 g / mol
Then the moles can easily be calculated by using the above formula ,
n = w / m
n = 20 g / 10 g/mol = 2 mol
Hence , answer = 2 mol.
Explanation:
An epidemic (from Greek ἐπί epi "upon or above" and δῆμος demos "people") is the rapid spread of disease to a large number of people in a given population within a short period of time.
Answer:
The Bohr Model is very limited in terms of size. Poor spectral predictions are obtained when larger atoms are in question. It cannot predict the relative intensities of spectral lines. It does not explain the Zeeman Effect, when the spectral line is split into several components in the presence of a magnetic field.
Explanation:
<h3><u>Answer;</u></h3>
When hydrogen is covalently bonded to an electronegative atom
<h3><u>Explanation;</u></h3>
- Hydrogen bonding is a special type of dipole-dipole attraction between molecules. It results from the attractive force between a hydrogen atom covalently bonded to a very electronegative atom such as a N, O, or F atom.
- Highly electronegative atoms attract shared electrons more strongly than hydrogen does, resulting in a slight positive charge on the hydrogen atom. The slightly positive hydrogen atom is then attracted to another electronegative atom, forming a hydrogen bond.
Answer:
2.5 g
Explanation:
Given data:
Masses of sample = 0.12 g, 1.8 g, 0.562 g
Combine mass of samples = ?
Solution:
When we add or subtract the values the number of significant figures after decimal in result must be equal to the given measurement having less number of decimal places.
0.12 g + 1.8 g + 0.562 g
2.482 g
In given three measurements 1.8 has less number of significant figure after decimal point which is only one digit. Thus the final value must contain one digit after decimal.
we will round of 2.482 g.
2.5 g
because the next digit after 4 is 8 that's why we will round 4 to 5.
