![heyItsLuna234](/avatars/3813.jpg)
heyItsLuna234
23.09.2019 •
Chemistry
Plz
25 grams of mg react with 20 grams of hcl. identify the limiting reagent. how much of the excess reagent remains? show your work.
Solved
Show answers
More tips
- G Goods and services How to Choose a Bread Maker?...
- A Art and Culture Who Said The Less We Love a Woman, the More She Likes Us ?...
- F Family and Home How to Get Rid of Your Neighbors?...
- S Society and Politics How Could Nobody Know About the Dead Mountaineers?...
- H Health and Medicine How to Cure Adenoids?...
- H Health and Medicine Why Wearing a Back Brace Can Be Beneficial During Back Strain?...
- S Sport When and Where Will the 2014 World Cup be Held?...
- C Computers and Internet How to Choose a Monitor?...
- H Horoscopes, Magic, Divination Where Did Tarot Cards Come From?...
Answers on questions: Chemistry
- C Chemistry My question my question...
- C Chemistry How many grams of water are produced from the decomposition of 63 grams of lithium hydroxide (LiOH)?...
- C Chemistry What volume of a 23.0% (W/V) solution of glycerol (C3H2O2) is required to prepare 2.400 liters of a 5.50% solution?...
- C Chemistry PLEASE HELP!!! A 24.5 g sample of sodium chloride reacts with 41.3 g of fluorine gas according to the following chemical equation. 2 NaCl(s) + F2(g) → 2 NaF(s) + Cl₂(g) a. What is...
- C Chemistry Choose all the right answers. The astroid belt separates the planets into two groups. Which planets are in the outter-most group away from the sun? Earth Saturn Mercury Uranus Neptune...
- C Chemistry When a beta particle is released from a nucleus of an atom: the number of electrons in the atom is increased the number of protons in the nucleus is increased the mass number of...
- C Chemistry What are two differences between status clouds and cirrus clouds...
- E English Which sentence shows correct subject-verb agreement? a. the girl eat her lunch together. b. the girl eat their lunch together. oc. the girls eats their lunches together. d. the girls...
- M Mathematics What is the third quartile of this data set? 20, 21, 24, 25, 28, 29, 35, 37, 39, 42, 44...
- H History What u.s. document was based on the english bill of rights?...
Ответ:
The limiting reagent is HCl.
18.42 grams of Mg, the excess reagent, will not react.
Explanation:
The limiting reagent is one that is consumed first in its entirety, determining the amount of product in the reaction. When the limiting reagent is finished, the chemical reaction will stop.
To know the limiting reagent, you must first know the amount of mass that reacts by stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction). For that, you must know the molar mass (mass of one mole) of each reagent present in the reaction. Then you must know the mass of each element that makes up the compound. This is obtained in the periodic table:
Mg: 24 g/molH: 1 g/molCl: 35.45 g/molThen:
Mg(s): 24 g/molHCl(aq): 36.45 g/molBy stoichiometry you can see that 1 mol of Mg (s) and 2 moles of HCl (aq) react. So the mass that reacts by stoichiometry is:
Mg(s): 24 g/molHCl(aq): 2*36.45 g/mol=72.9 g/molThe rule of three or is a way of solving problems of proportionality between three known values and an unknown value, establishing a relationship of proportionality between all of them. That is, what is intended with it is to find the fourth term of a proportion knowing the other three. Remember that proportionality is a constant relationship or ratio between different magnitudes.
If the relationship between the magnitudes is direct, that is, when one magnitude increases, so does the other (or when one magnitude decreases, so does the other) , the direct rule of three must be applied. To solve a direct rule of three, the following formula must be followed:
a ⇒ b
c ⇒ x
The rule of three can be used to calculate the limiting reagent as follows: if by stoichiometry 72.9 grams of HCl react with 24 grams of Mg, then if 20 grams of HCl react how many grams of Mg are required?
mass of Mg≅6.58 grams
But you have 25 grams of Mg available. That is, you have more mass available than are necessary to react with 20 grams of HCl. This means that Mg is the excess reagent. Therefore the limiting reagent is HCl.
But you have 25 grams of Mg available and only 6.58 grams are necessary to react with 20 grams of HCl. Then with a simple subtraction you can calculate the mass that does not react:
Mass remaining = 25 grams - 6.58 grams = 18.42 grams
Mass remaining = 18.42 grams
18.42 grams of Mg, the excess reagent, will not react.
Ответ: