What energy is needed to make evaporation happen

The atomic number tells us how many __ or __ an element contains.

CaHeK987 [17]

Answer:-
Electrons or Protons

Explanation:-
Atomic number (Z) is defined as:
>>“The total number of protons in the nucleus of an atom is called atomic number”. All atoms of an element have the same number of protons and electrons.
>>“The total number of protons in the nucleus or electrons revolving around the nucleus of an atom”.
Example:
For instance, Hydrogen has the Atomic number(Z) 1.
Helium has the atomic number 2.
Oxygen has the atomic number 8.
| Note | Atomic number is represented by “Z”. And some ppl don’t consider the 2nd definition it’s upto u to do both or the standard one.

5 0

3 years ago

A 0.0000792 M sample of Compound X in a solvent has an absorbance of 0.341 at 528 nm in a 1.000-cm cuvet. The solvent alone has

natima [27]

Answer:

a) a = 3485 M⁻¹cm⁻¹

b) C = 0,000127 M

Explanation:

Lambert-Beer law says that there is a linear relationship between absorbance and concentration of a chemical substance. The formula is:

A = a×b×C

Where A is absorbance, a is molar absorptivity, b is path length and C is concentration.

a) In the problem Concentration is 0.0000792 M, b is 1,000cm and Absorbance is absorbance of sample-absorbance of blank: 0,341-0,065 = 0,276

Replacing:

0,276 = a×1,000cm×0,0000792M

a = 3485 M⁻¹cm⁻¹

b) As the experiment consist in the same compound in the same solvent, the molar absorptivity will be the same, a = 3485 M⁻¹cm⁻¹, path length will be 1,000cm and absorbance: 0,508-0,065 = 0,443

Replacing:

0,443 = 3485 M⁻¹cm⁻¹×1,000cm×C

C = 0,000127 M

I hope it helps!

8 0

3 years ago

What did alexander fleming discover that earned him the 1945 novel prize of medicine?

Leviafan [203]

He discovered penicillin

6 0

3 years ago

Which one of the following metals would NOT displace hydrogen from a dilute solution of HCl? 1. Ag 2. Fe 3. Al 4. Ni

jolli1 [7]

Answer:

Ag

Explanation:

To determine which element will displace hydrogen from a dilute acid, we need to make reference to the activity series or the electrochemical series. The activity series is a list of metallic ions according to their electropositivity.

This means elements are ranked here based on how electrically positive they are. Hence, an element above another element is relatively more electropositive than the one under it. For example calcium is less electropositive compared to sodium as calcium is found under sodium in the list.

Now, for an element to displace hydrogen, it means the particular element is more electropositive than hydrogen on the activity series. All the elements in the options are in a greater position relative to hydrogen on the activity series except silver. This means it cannot displace hydrogen from a dilute mineral acid

7 0

4 years ago

Full net ionic equation of nitric acid and solid aluminum hydroxide please

atroni [7]

Is ionic equation . nitric acid + solid aluminium = hydroxide.

4 0

3 years ago