I believe the answer is carbon dioxide
D. A mixture
If the water is evaporating while the salt remains, it means the two are not chemically bonded and therefore are not a compound.
Answer:
D. 15g
Explanation:
The law of conservation of mass states that, in a chemical reaction, mass can neither be created nor destroyed. This means that the amount of matter in the elements of the reactants must be equal to the amount in the resulting products.
In this question, 25 grams of a reactant AB, was broken down in a reaction to produce 10 grams of products A and X grams of product B. According to the law of conservation of mass, the mass of the reactant must be equal to the total mass of the products. This means that 25 grams must also be the total mass of both products in this reaction. Hence, if product A is 10 grams, product B will be 25 grams - 10 grams = 15 grams.
Therefore, product B must be 15 grams in order to form a total of 25 grams when added to the mass of product A. This will equate the mass of the reactant AB and fulfill the law of conservation of mass.
An ion is a charged atom or molecule. It is charged because the number of electrons do not equal the number of protons in the atom or molecule. An atom can acquire a positive charge or a negative charge depending on whether the number of electrons in an atom is greater or less then the number of protons in the atom. An example is Iron (III) , Iron (II) , lithium, and hydrogen.
Answer : The volume of stock solution needed are, 12.5 mL
Explanation :
Formula used :

where,
are the initial molarity and volume of copper (II) chloride.
are the final molarity and volume of stock solution of copper (II) chloride.
We are given:

Putting values in above equation, we get:

Hence, the volume of stock solution needed are, 12.5 mL