The question is incomplete.
You need two additional data:
1) the original volume
2) what solution you added to change the volume.
This is a molarity problem, so remember molarity definition and formula:
M = n / V in liters: number of moles per liter of solution
To give you the key to answer this kind of questions, supppose the original volumen was 1 ml and that you added only water (solvent).
The original solution was:
V= 1 ml
M = 0.2 M
Using the formula for molarity, M = n / V
n = M×V = 0.2 M × (1 / 10000)l = 0.0002 moles
For the final solution:
n = 0.0002 moles
M = 0.04
From M = n / V ⇒ V = n / M = 0.002 moles / 0.04 M = 0.05 l
Change to ml ⇒ 0.05 l × 1000 ml / l = 50 ml. This would be the answer for the hypothetical problem that I assumed for you.
I hope this gives you all the cues you need to answer similar problems about molarity.
Answer:
See explanation
Explanation:
The question is incomplete because the images of the models are absent. However, i will try to give you a general description of what the correct answer should be.
Beryllium is a member of group 2 in the periodic table. Beryllium has an atomic number of 4. This implies that it has four protons in its nucleus and four electrons in its shells. In a neutral atom, the number of electrons on the shells is equal to the number of protons in the nucleus.
The electronic configuration of Beryllium is 1s2 2s2. This implies that it should have two shells each containing only two electrons each.
Since we are using white foam balls for protons and black foam balls for neutrons, the clear plastic will contain four white foam balls and five black foam balls since the mass number of beryllium is 9 and number of neutrons = mass number - number of protons.
Four blue foam balls hanging from strings will represent the electrons around the nucleus.
Any model that corresponds to the description above is the correct answer.
Answer:
Explanation:
Here, we want to get the equation of the reaction between Hydrochloric acid and Zinc metal
Zinc metal displaces the hydrogen from hydrochloric acid to form zinc chloride
We have the equation of reaction as:
Answer:
The answer is 375.54 g of AgBr
Explanation:
Mass (g) = Concentration (mol/L) x volume (L) x Molecular Weight of AgBr (g/mol)
Mass = 2M x 1L x 187.77 g/mol
Mass = 375.54g
Answer:
Distance between the carbon atom = 491 pm
Explanation:
Given:
1 pm = 1 × 10⁻¹² m
Distance between the carbon atom = 2.81 × 10⁻⁸ cm
Find:
Distance in picometers
Computation:
Distance between the carbon atom = 2.81 × 10⁻⁸ cm = 491 X 10⁻¹² m
Distance between the carbon atom = 491 pm
