Answer:
The correct choices are:
- <em>using accurate measurements</em>
- <em>using pure chemicals</em>
- <em>performing the reaction under the most ideal conditions</em>
Explanation:
The theoretical yield is the maximum amount of product that could be obtained by the chemical reaction, from a given amount of reactants. You calculate the theoretical yield using the stoichiometry coefficients of the balanced chemical equation.
The <em>percent yield </em>is the ratio of the actual yield (the actual amount obtained) of a product to the theoretical yield for the same product, expressed as a percentage (i.e. multiplied by 100).
- percent yield = actual yield × 100 / theoretical yield
As the actual yield decrease (the numerator of the ratio), the percent yield decrease.
To increase the percent yield it is important:
- using accurate measurements
- performing the reaction under the most ideal conditions
<em><u>Using accurate measurements:</u></em> if you do not add the correct amounts of each reactant, then the product obtained will not be what you can predict from the theoretical calculations and you will be wasteing one or other reactant, without reaching the maximum yield possible.
<em><u>Using pure chemicals:</u></em> if the chemicals are not pure, the amount of actual reactants will be lower than they should be, leading to a lower actual yield.
<em><u>Performing the reaction under the most ideal conditions:</u></em> the actual rate of reactions depend on the conditions: temperature and pressure are the most commons. Since, temperature and pressure may change that rate of reactions, you should find and use the most ideal conditions to get the greatest actual yield.
<em>Adding water</em>, can just dilute the reactants and would decrease the rate of reaction, which would not be helpful to increase the yield.
Answer:
Ventilator
Explanation:
What is the WHMIS 1988 classification? ... Symbol for Class D1 ... Direct contact with the liquefied gas can chill or freeze the skin (frostbite). ... Take precautions to ensure your own safety before attempting rescue (e.g. wear ... Increase ventilation to area or move leaking container to a well-ventilated and secure area.
So B. is the Right Choice!
Answer:
Invasive species are an organism that causes ecological or economic harm in a new environment where it's not native.
Explanation:
An invasive species can harm both the natural resources in the ecosystem as well it threaten the human use of these resources and invasive species can be introduced to a new area via the ballast water of oceangoing ships, intentional and accidental releases of aquaculture species, aquarium specimens or bait, and etc.
Invasive species is capable of causing extinctions to native plants and animals, reducing biodiversity, competing with native organisms for limited resources, and altering habitats. This can also result a huge economic impacts and fundamental disruptions of coastal and the great lakes of the ecosystems.
I hope it helps you.
Answer:
c
Explanation:
Nh4OH + HCL ---> NH4Cl + H3O
so ph decreases as H3O increases
and OH also decreases