The answer is 33.33 %
The explanation:
According to the reaction equation:
MgCO3(s) + 2HCl (aq) --> MgCl2(aq) + H20(l) + CO2(g)
we can see that 1 mole of MCO3 will produce → 1 mole of CO2
-Now we need o get number of mole of CO2:
and when we have 0.22 g of CO2, so number of mole = mass / molar mass
moles = 0.22 g / 44 g/mol = 0.005 mole
∴ moles of Mg = moles of CO2 = 0.005 mole
∴ mass of Mg = moles * molar mass
= 0.005 * 84 /mol = 0.42 g
∴ Percent of MgCO3 by mass of Mg = 0.42 g / 1.26 * 100
= 33.33 %
The factors that limit a technological design can be physical and social. The physical limitations are constraints due to nature itself. They include natural laws and properties of materials.
Social limitations on the other hand are limitations that arise as a result of the society we are living in and include the ease of use, safety, attractiveness, and cost.
Since the nucleophile is the actual attacking molecule or molecule that starts the reaction and allows for further steps in the mechanism to occur, it is the limiting reagent, as based on the amount of the nucleophile you have, the reaction will tend to proceed until you run out. The excess would be the sodium hydroxide, it is union part of the solution.
Answer:
A. They must be kept separate from moisture and oxygen
Explanation:
Alkali metals refers to a group of chemical elements in the periodic table. It is the common name given to Group 1 elements (excluding hydrogen). They are generally metallic in nature with physical properties like shining lustre, silvery in appearance etc. Alkali metals include lithium, Pottasium, Sodium, Rubidium etc.
One important chemical property of alkali metals is their high reactivity i.e. they tend to react quickly with other substances. For example, alkali metals react vigorously with water to form hydroxides. They also react with oxygen to form oxides. Due to this highly reactive properties, they are kept or stored away from moisture (water) and oxygen (present in air).
An environmental scientist studies the environment - you can see that in the beginning of the sentence :)
