Answer:
Solid
Explanation:
In solid there are strong intermolecular forces present as compared to liquid and gas. This is why solid are in more packed form as compared to liquid and gas. In liquid and gas intermolecular forces are week that's why molecules are away from each other and occupy more space.
Properties of gases:
Molecule of gases randomly move everywhere and occupy all available space.
Gases don't have definite volume and shape and take the shape and volume of container in which it present.
Their densities are very low as compared to the liquid and solids.
Gas molecules are at long distance from each other therefore by applying pressure gases can be compressed.
The very weak inter molecular forces are present between gas molecules.
Properties of Liquid:
Liquid have definite volume but don't have definite shape.
Their densities are high as compared to the gases but low as compared to the solids.
In liquid, molecules are close to each other and have greater inter molecular forces as compared to the gas molecules.
Properties of solids:
Solids have definite volume and shape.
In solids molecules are tightly pack and very close to each other.
Their melting and boiling point are every high.
The densities of solids are also very high as compared to the liquid and gas.
There are very strong inter molecular forces are present between solid molecules.
Answer:
Explanation:
combustion reacts with oxygen
You have to calculate the oxidation estates of the atoms in each compound.
I will start with K2Cr2O7 because I believe that Cr is the best candidate to reduce its oxidation number in 3 units.
In K2Cr2O7:
- K has oxidation state of 1+, then K2 has a charge of 2* (1+) = 2+.
- O has oxidation state of 2*, then O7 has a charge of 7* (2-) = 14-.
That makes that Cr2 has charge of 14 - 2 = +12, so each Cr has +12/2 = +6 oxidation state.
In Cr2O3:
- O has oxidation state of 2-, then O3 has charge 3 * (2-) = - 6
- Then, Cr2 has charge 6+, and each Cr has charge 6+ / 2 = 3+.
So, we have seen that Cr reduced its oxidation state in 3 units, from 6+ to 3+.
Answer: Cr has a change in oxidation number of - 3.
Answer:
250 mL (total solution) = 104 mL (stock solution) + 146 mL (water)
Explanation:
Data Given
M1 = 6.00 M
M2 = 2.5 M
V1 = 250 mL
V2 = ?
Solution:
As the chemist needs to prepare 250 mL of solution from 6.00 M ammonium hydroxide solution to prepare a 2.50 M aqueous solution of ammonium hydroxide.
Now
first he have to determine the amount of ammonium hydroxide solution that will be taken from6.00 M ammonium hydroxide solution
For this Purpose we use the following formula
M1V1=M2V2
Put values from given data in the formula
6 x V1 = 2.5 x 250
Rearrange the equation
V1 = 2.5 x 250 /6
V1 = 104 mL
So 104 mL is the volume of the solution which we have to take from the 6.00 M ammonium hydroxide solution to prepare 2.5 M aqueous solution of ammonium hydroxide
But we have to prepare 250 mL of the solution.
so the chemist will take 104 mL from 6.00 M ammonium hydroxide solution and have to add 146 mL water to make 250 mL of new solution.
in this question you have to tell about the amount of water that is 146 mL
250 mL (total solution) = 104 mL (stock solution) + 146 mL (water)
I believe it is b. you only want to change one thing at a time so you know which one thing caused the effect