Answer:
The percentage yield of LiOH is 39.9%
Explanation:
From the question given above, the following data were obtained:
Theoretical yield = 47.4 g
Actual yield = 18.9 g
Percentage yield =?
The percentage yield of LiOH can be obtained as follow:
Percentage yield = Actual yield / Theoretical yield × 100
Percentage yield = 18.9 / 47.4 × 100
Percentage yield = 1890 / 47.4
Percentage yield = 39.9%
Therefore, percentage yield of LiOH is 39.9%
Question 10.
Which of the following are agricultural implements?
(a) Seed drills
(b) Silos
(c) Harrow
(d) All of these
How many elements of oxygen are present in the molecule below 3Ca(OH)2
Answer:
Two elements of oxygen are presented.
ASAP. Which process represents a physical change?
1.Roasting a marshmallow over a camp fire
2.Melting chocolate in a pan on the stove
3.Bruising of a banana's skin after dropping on the floor
4.Bubbling due to an antacid tablet in vinegar
If you had 6H2 molecules and 4O2 molecules, how many H2O molecules could you produce?
Answer:
6
Explanation:
As , 2H2 + O2 = 2H2O
with 6 H2, 4O2 is excess.
H2O molecules formed = 6
If a gas is cooled from 315 K to 231 K, what was its initial pressure if its final pressure is 625 torr?
Answer:
The initial pressure was 852.27 torr.
Explanation:
Given that,
Initial temperature, T = 315 K
Final temperature, T' = 231 K
Final pressure, P' = 625 torr
We need to find the initial pressure of the gas. We know that, the relation between pressure and temperature is given by :
[tex]\dfrac{P}{P'}=\dfrac{T}{T'}\\\\P=\dfrac{P'T}{T'}\\\\P=\dfrac{625\times 315}{231}\\\\P=852.27\ torr[/tex]
So, the initial pressure was 852.27 torr.
Why should you prefer dry-ashing to wet-ashing of a food sample such as
cabbage?
Can someone pls answer this question
Somebody please helppppppppppp
Answer:
B. Trees can be replenished
Explanation:
Trees are renewable and replenishable resources. Trees can be planted, grown up, and harvested for timber.
A popular classroom demonstration consists of filing notches into a new penny and soaking the penny in hydrochloric acid overnight. Because new pennies are made of zinc coated with copper, and hydrochloric acid dissolves zinc and not copper, the inside of the penny is dissolved by the acid, while the outer copper shell remains. Suppose a penny contains 2.5 g of zinc and is soaked in 20.0 mL of 6.0 M HCl. Calculate the concentra- tion of the HCl solution after all of the zinc has dissolved. Hint: The Zn from the penny is oxidized to Zn2
Answer:
[tex]HCl conc=2.2M[/tex]
Explanation:
From the question we are told that:
Mass of zinc [tex]Mass_{z_n}=2.5g[/tex]
Initial conc of HCl [tex]HConc_1=6.0M[/tex]
Initial volume of HCl [tex]Hvol_1=20.0mL[/tex]
Molar mass of zinc [tex]M_{Z_n}=65.38g/mol[/tex]
Generally the equation for reaction is mathematically given by
[tex]2HCL+Zn\implies ZnCl_2 +H_2[/tex]
Generally the equation for moles of zinc [tex]m_{z_n}[/tex] is mathematically given by
[tex]m_{z_n}=\frac{Mass_{Z_n}}{M_{Z_n}}[/tex]
[tex]m_{z_n}=\frac{2.5g}{M_{65.38}}[/tex]
[tex]m_{z_n}=0.038molZn[/tex]
Generally the equation for moles of [tex]m_{HCl}[/tex] is mathematically given by
[tex]m_{HCl}=HConc_1*Hvol_1[/tex]
[tex]m_{HCl}=6.0M*20.0mL[/tex]
[tex]m_{HCl}=6.0M*20.0*10^{-3}L[/tex]
[tex]m_{HCl}=0.12\ mol\ HCl[/tex]
Generally the reacted moles of HCl [tex]HCl_[reacted][/tex] is mathematically given by
Since
Zn:HCl =1:2
Therefore
[tex]HCl_[reacted]=0.038*\frac{2}{1}[/tex]
[tex]HCl_[reacted]=0.076mol \ HCl[/tex]
Generally the moles of HCl after Zn oxidization X is mathematically given by
[tex]x=0.12-0.076[/tex]
[tex]x=0.044 mol HCl[/tex]
Generally the conc of hydrochloride acid X is mathematically given by
[tex]X=\frac{0.044}{0.020}[/tex]
[tex]X=2.2 M Hcl[/tex]
Therefore Conc of HCl
[tex]HCl conc=2.2M[/tex]
A balloon with an initial volume of 3.5 L at a temperature of 296 K is warmed to 376 K
What is its volume at 376 K?
Answer:
4.4 L
Explanation:
From the question given above, the following data were obtained:
Initial volume (V₁) = 3.5 L
Initial temperature (T₁) = 296 K
Final temperature (T₂) = 376 K
Final volume (V₂) =?
The final volume of the balloon can be obtained by using the Charles law equation as illustrated below:
V₁ / T₁ = V₂ / T₂
3.5 / 296 = V₂ / 376
Cross multiply
296 × V₂ = 3.5 × 376
296 × V₂ = 1316
Divide both side by 296
V₂ = 1316 / 296
V₂ = 4.4 L
Thus, the final volume of the balloon is 4.4 L
Which of the following systems helps get rid of some kind of waste?
A
excretory system
B
digestive system
C
respiratory system
D
all of the above
The system which helps in get rid of some kind of waste are excretory system, digestive system and respiratory system.
What are waste materials?Waste materials are the substances which we will get after the absorption of all nutients and usefull things.
Excretory system helps in the removal of waste in the form of stool.Digestive system helps in the removal of waste material to the excretory system after breaking the organic molecules into small molecules.Respirartory system helps in the removal of carbon dioxide gas.Hence all above given systems helps to get rid of some kind of waste.
To know more about excretory system, visit the below link:
https://brainly.com/question/16665730
#SPJ2
If electric current is passed through aqueous LiBr, the product at the cathode would be __________ and the product at the anode would be __________.
a) H2O(l), Li+(aq)
b) Br2(l), Li(s)
c) Li(s), Br2(l)
d) Br2(l), H2(g)
e) H2(g), Br2(l)
When the gas shown in the Energy Distribution diagram is heated to "T2," what has happened?
Select all that apply.
The average kinetic energy has lowered.
The average kinetic energy has increased.
o The highest energy level has decreased.
Less molecules have a higher energy level.
More molecules have a higher energy level.
Answer:
The average kinetic energy has increased. More molecules have a higher energy level.
Explanation:
I so esay
Ionisation enthalpy across the group (increase or decrease)
Give reasons??
Answer:
As we move from left to right across a period, the ionization energy of elements increases. This is due to the decrease in the size of atoms across a period.
Answer:
[tex]\huge\boxed{Answer\hookleftarrow}[/tex]
Ionization enthalpy (IE) is the energy required to remove the highest-energy electron from a neutral atom. In general, ionization energy increases across a period and decreases down a group.So, for your question ⇻ IE decreases down the group.____________________
ʰᵒᵖᵉ ⁱᵗ ʰᵉˡᵖˢ
# ꧁❣ RainbowSalt2²2² ࿐
names the process which takes place when a red litmus paper turns white when dropped into chlorine water
Answer:
Answer. Explanation: Chlorine gas bleaches the damp litmus (red or blue). Bleaching is an oxidation process.
In the outline of the Periodic Table below, some elements are shown as numbers.
Which two numbers are metals in the same period?
Answer:
5 and 6
Explanation:
Answer:
3 and 4
Explaination:
The metals are Sodium and Phosphorus respectively which are in period 2 of the periodic table but in different groups.
An experiment shows that a 236 mL gas sample has a mass of 0.443 g at a pressure of 740 mmHg and a temperature of 22 ∘C. What is the molar mass of the gas?
Answer:
49.2 g/mol
Explanation:
Let's first take account of what we have and convert them into the correct units.
Volume= 236 mL x ([tex]\frac{1 L}{1000 mL}[/tex]) = .236 L
Pressure= 740 mm Hg x ([tex]\frac{1 atm}{760 mm Hg}[/tex])= 0.97 atm
Temperature= 22C + 273= 295 K
mass= 0.443 g
Molar mass is in grams per mole, or MM= [tex]\frac{mass}{moles}[/tex] or MM= [tex]\frac{m}{n}[/tex]. They're all the same.
We have mass (0.443 g) we just need moles. We can find moles with the ideal gas constant PV=nRT. We want to solve for n, so we'll rearrange it to be
n=[tex]\frac{PV}{RT}[/tex], where R (constant)= 0.082 L atm mol-1 K-1
Let's plug in what we know.
n=[tex]\frac{(0.97 atm)(0.236 L)}{(0.082)(295K)}[/tex]
n= 0.009 mol
Let's look back at MM= [tex]\frac{m}{n}[/tex] and plug in what we know.
MM= [tex]\frac{0.443 g}{0.009 mol}[/tex]
MM= 49.2 g/mol
Which is the best example of a new substance forming?
cutting a piece of paper
lighting a match
popping a balloon
hitting a nail with a hammer
Specific heat is a common name for which of the following?
Answer:
heat capacity. (another term used for specific heat)The amount of heat required to raise the temperature of a specified amount of a substance by 1°C or 1 K.
Explanation:
Specific heat is a common name for:
Massic heat capacitySpecific heat is the term that is used to describe the amount of heat which would be sufficient to change the temperature of a unit mass by one degree.
As a result of this, we can see that if the specific heat that is needed to change the temperature of water is found, then it can be easily determined if the water has reached its boiling point.
Therefore, another name for specific heat is also massic heat capacit
Please note that your answer is incomplete and as a result of this, i would be giving you a general overview which should help you get the correct answer.
Read more here:
https://brainly.com/question/17188200
How many molecules are in 3 moles of CO2?
O A. 5.418 x 1024
OB. 1.806 x 1024
O C. 6.02 x 1024
O D. 1.806 x 1023
Answer:
1.806 × 10²⁴Explanation:
The number of molecules can be found by using the formula
N = n × L
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
N = 3 × 6.02 × 10²³
We have the final answer as
1.806 × 10²⁴Hope this helps you
Answer: OB. 1.806 x 1024
Explanation:
HELP !! Which statement describes a periodic trend of electronegativity?
A. Electronegativity increases from right to left across a period.
B. Electronegativity increases from left to right across a period.
C. Electronegativity increases from top to bottom of a group.
D. Electronegativity remains the same within a period.
Answer:
B
Explanation:
balance Al2O3 + NaOH + H2O = NaAl(OH)4
Answer:
Al₂O₃ + 2 NaOH + 3 H₂O = 2 NaAl(OH)₄
Create a graphic organizer describing types of substances including the difference between pure substance and mixture with subtypes and examples.
SCAM ANSWERS WILL BE DELETED.
If you answer this seriously I will P.A.y.P.a.l you 2 dollars. just leave them in the comments of your answer
Answer:
Pure substances are further divided into elements and compounds. The combination of two or more pure substances is called a mixture. Mixtures can be classified into two types viz. heterogeneous and homogeneous mixtures.
Explanation:
number of proton of gold
Answer:
English Language Learners Definition of number. (Entry 1 of 2) : a word or symbol (such as "five" or "16") that represents a specific amount or quantity. : a number or a set of numbers and other symbols that is used to identify a person or thing.
Explanation:
79 is the number of protons gold has.
Hope this helps; have a great day!
How do autotrophs and heterotrophs relate to the carbon cycle?
Answer:
Autotrophs store chemical energy in carbohydrate food molecules they build themselves. Most autotrophs make their food through photosynthesis using the energy of the sun. Heterotrophs cannot make their own food, so they must eat or absorb it.
Calculate the amount (in moles) of magnesium in 1.23 g.
Answer
0.32 is that answer
Explanation:
you just use the calculator
The purpose of a generator is to convert:
A. electrical energy to mechanical energy.
B. mechanical energy to electrical energy.
C. chemical energy to nuclear energy.
D. mechanical energy to chemical energy.
Answer:
b (mechanical energy to electrical energy)
Answer:
because mechanical energy is the generator. And it's majority is to convert mechanical energy to electrical energy
Calculate the mass in grams of a 1.070 mole of acetylene ,C2H2
Answer:
27.86x10^-3 Kg
Explanation:
Hi! To get the result you only need to use this formula: m = n x M <=> m = 1.070 x ((2x12.01 + 2x1.01) x 10^-3) = 27.8628 x 10^-3 Kg. Hope it helped!
How many liters of 3.0 MNAOH solution will react with 2.4 mole H2 S04
Please answer! Tap on the photo❤️
Answer:
E
Explanation:
no of grams in picture c = A+B
= 200+10 =210
for D its also 210 ..... the water already contains the salt .....so the mass of salt has added to the mass of water which is still 210
that's all .... have fun