The chemical reaction is written as:
2Zn + O2 = 2ZnO
We are given the amount of the product to be produced from the reaction. We use this value and the relation of the substances in the reaction to calculate what is asked. We do as follows:
2.10 g ZnO ( 1 mol / 81.408 g ) ( 1 mol O2 / 2 mol ZnO ) ( 32 g / 1 mol ) = 0.414 g O2 is needed
Answer:
a. glucose in water( solution)
b. smoke in air (colloids)
c. carbon dioxide in air (solution)
d. milk( colloids)
Explanation:
A solution is said to be formed when a solute dissolves in a solvent to form a homogeneous mixture. The solute particles are less than 10^-9m in size. Familiar solutions are those where the solute are dissolved in a liquid solvent. When the liquid water, the solution is known as an aqueous solution. A typical example is (glucose in water). In some other cases, the apparent solution of a solute in a solvent is accompanied by a chemical reaction and this is often known as a chemical reaction. A typical example is (carbon dioxide in air).
Colloids are also known as false solutions. Here, the individual solute particles are larger than the particles of the true solution, but not large enough to be seen by the naked eye. When a light beam is placed beside a beaker containing a colloid, the light rays of the beam can be clearly seen. This shows that it exhibits the Tyndall effect while a solution dosent exhibit such.
In a colloid, the liquid solvent is more appropriately know as the DISPERSION medium while the solid solute particles constitute the DISPERSED substance. This can either be solid, liquid or gas.
For example:
--> smoke in air : Dispersion medium is gas while the dispersed substance is solid.
--> milk: Dispersion medium is liquid while the dispersed substance is liquid.
Sulfur and chlorine. Explanation: A covalent bond is formed by two non-metals with similar electronegativities. As a consequence, they share one or more pairs of electrons between their nuclei
M1m1 = M2m2
where M1 is the concentration of the stock solution, m1 is the
mass of the stock solution, M2 is the concentration of the new solution and
m2 is its new mass.
M1m1 = M2m2
.925(m1) = .35(250)
m1 = 94.59 g
