State two procedures which should be used to properly handle a light microscope

KengaRu [80]

Answer:

Bohr's model of the hydrogen atom is based on three postulates:

1) An electron moves around the nucleus in a circular orbit,

2) An electron's angular momentum in the orbit is quantised,

3) The change in an electron's energy as it makes a quantum jump from one orbit to another is always accompanied by the emission or absorption of a photon. Bohr's model is semi-classical because it combines the classical concept of electron orbit (postulate 1) with the new concept of quantisation ( postulates 2 and ).

4 0

3 years ago

A glass column is filled with mercury and inverted in a pool of mercury. The mercury column stabilizes at a height of 729 mm abo

harkovskaia [24]

The atmospheric pressure will be:

The pressure of the atmosphere resulting from the mercury column is 0.959 atm

What is atmospheric pressure?

The force that an object experiences from the weight of the air above it per unit area are known as atmospheric pressure.

Given: Height of mercury column = 729 mm Hg

To find: The pressure of the atmosphere

Calculation:

The atmospheric column resulting from the mercury column is calculated as follows:

1 atm =760 mm Hg

So, we can convert the 729 mm Hg to atm, and we get

Atmospheric pressure = 729 x 1 atm / 760 = 0.959 atm

Learn more about atmospheric pressure here,

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5 0

1 year ago

Draw the Lewis structure for BCl3. How many single bonds, double bonds, triple bonds, and unshared pairs of electrons are on the

andreev551 [17]

Answer : The number of single bonds, double bonds, triple bonds, and unshared pairs of electrons on the central atom are, 3, 0, 0 and 0 respectively.

Explanation :

Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.

In the Lewis-dot structure the valance electrons are shown by 'dot'.

The given molecule is, $BCl_3$

As we know that boron has '3' valence electrons and chlorine has '7' valence electrons.

Therefore, the total number of valence electrons in $BCl_3$ = 3 + 3(7) = 24

According to Lewis-dot structure, there are 6 number of bonding electrons and 18 number of non-bonding electrons.

From the Lewis-dot structure we conclude that,

The number of single bonds, double bonds, triple bonds, and unshared pairs of electrons on the central atom are, 3, 0, 0 and 0 respectively.

3 0

3 years ago

2.600 * 10 ^ - 5 * 6.100 * 10 ^ - 5 Express in scientific notation

Anna [14]

Answer:

hope its help you

Explanation:

2.600 × 10^-5 × 6.100 × 10^-5 = 1.586 × 10-9

3 0

3 years ago

IF YOURE GOOD AT CHEMISTRY PLEASE HELP ILL MARK YOU BRAINLIEST

ratelena [41]

A solute is the substance to be dissolved (sugar). The solvent is the one doing the dissolving (water). The amount of solute that can be dissolved by the solvent is defined as solubility. Water can form a gas f hotnot heated and if you put something cold in the water that has that was formed can be dissolved by that cold substance.

6 0

3 years ago