A white insoluble solid would appeaer
Answer:
gold wire (Au)
Explanation:
A substance that cannot be separated or broken down into simpler substances by chemical means is an element.
Between the given options only gold wire is an element, Au.
A way of knowing that it is an element is noticing that its formula is a single symbol which corresponds to an element found in the periodic table, unlike a combination of said symbols (like NaCl or H₂O).
Answer: Option (b) is the correct answer.
Explanation:
A solution whose constituent particles are uniformly distributed in the solution is known as a homogeneous solution.
In a homogeneous solution, particles of one solute completely dissolves in the solvent. This solution is also known a true solution.
When sand and water are mixed together then after a certain interval of time sand particles will settle at the bottom. Therefore, they do not dissolve in water. So, it is not a homogeneous solution.
When salt and water are mixed together then the salt particles will dissolve in water. Therefore, it is a homogeneous solution.
Salad dressing is not a homogeneous solution as it contains different solutions like oil, lemon juice etc which does not dissolve when mixed together.
On the other hand, soil is also not a homogeneous solution because we can visualize the distinct layers present in a soil. These layers when mixed in a solution does not dissolve so they did not form a homogeneous solution.
Thus, we can conclude that out of the given options, salt and water is a homogeneous mixture.
<u>Answer:</u> The volume of stock solution of calcium chloride required is 10 mL.
<u>Explanation:</u>
A solution consists of solute and solvent. A solute is defined as the component that is present in a smaller proportion while the solvent is defined as the component that is present in a larger proportion.
To calculate the amount of solute needed, the formula used is:
....(1)
where,
are the concentration and volume of stock solution of calcium chloride
are the concentration and volume of diluted solution of calcium chloride
Given values:
Plugging values in equation 1:
Hence, the volume of stock solution of calcium chloride required is 10 mL.
