CaseAnswer:
-Mole of stearic acid used = 1.3*10^-3 mol
-Molecules of stearic acid there would be in 1 mole of stearic acid = 7.994*10^20 molecules
Explanation:
Know information from the problem are:
Mass concentration of C18H32O2 = 1.6x10^-4 g/ml, Molar mass of C18H32O2 = 284 g/mol.
Unit factor from drops to ml is 72 drops = 1ml. Therefore, for every drop, n, given, there would be n drops (1ml/ 72drops). The problem tells that stearic acid was added to hexane and that the addition process was done three-time with different amounts of drops. Think of this as releasing a substance from a burette during titration. If we convert the drops into millimeters, we would have 20 drops (1ml/72drops)= 0.28 ml, 21 drops (1ml/72drops)= 0.29 ml, and 16 drops (1ml/72drops)= 0.22 ml. [We need these volumes to determine the mass of stearic acid from mass concentration given.]
Unknown informations are:
V (volume in ml) =?
The mole of stearic acid used =?
Strategy
To calculate the mole of stearic acid used, we need the mass of stearic acid from the mass concentration. To get this we need a volume. Notice that those volumes (drops) are not the same ( it is safe to say that there is an error in the readings, as they were done independently). Therefore, we would find two or three values whose difference is smaller ( there is a little error). Subtract the smaller number from the larger number till you get a smaller difference ( do this for all three values).
The set of numbers with the smallest difference is 0.29 - 0.28=0.014, our concordant value.
Solutions
Now we us this set of numbers, 0.29-0.28, to determine an average volume :
V = (0.29-0.28)/2 (ml)
V= 0.285 ml
Now we can calculate the mass of stearic acid from the mass concentration:
m = C*V; m is the mass, C is the concentration in g/ ml, and V is the volume in ml.
m = (1.64*10^-4 g/ml)*(0.285 ml)
m = 4.674*10^-5 g
The mole of stearic acid used:
n = m/MM l; n is the mole of stearic acid, m is the mass of stearic acid, and MM is the molar mass of stearic acid.
n = 4.674*10^-5 g (284 g/mol)
n = 1.3274*10^-3
How many molecules of stearic acid would there be if it was 1 mol of stearic acid?
1 mol = 6.02214*10^23 molecule
Therefore, a conversion fraction would be:
6.02214*10^23 molecule/ 1 mol
Solution
Molecules of stearic acid in 1 mol =
1.3274*10^-3 mol (6.02214*10^23 molecule/ 1 mol)
= 7.994*10^20 molecules in 1 mol of C18H16O2
What is the volume of a container that contains 12.6 grams of nitrogen at 25°C and 1100 kPa?
Answer:
1.0 L
Explanation:
Use the ideal gas law PV=nRT where P is pressure = 1100 kPa, V is the volume you are calculating, n is the number of moles which can be calculated by dimensional analysis and the periodic table, R is the ideal gas constant in this case R=8.314 kPa L/K mol, and T is the temperature in kelvins. See attached image for work through. 1.0 L is the answer with two sig figs.
Deforestation affects which of the following?
O none of the cycles
Owater cycle and carbon cycle
O carbon cycle only
O water cycle only
Answer:
water cycle and carbon cycle
Five liters of air at -35°C is warmed to 89°C. What is the new volume if the pressure remains constant
Answer:
7.61 liters
Explanation:
From the question,
Applying Charles law formula,
V₁/T₁ = V₂/T₂...................... Equation 1
Where P₁ = initial volume of of air, V₂ = Final volume of air, T₁ = Initial Temperature of air, T₂ = Final Temperature of air.
make V₂ the subject of the equation
V₂ = (V₁×T₂)/T₁............... Equation 2
Given: V₁ = 5 liters, T₁ -35 °C = (-35+273) K = 238 K, T₂ = 89°C = (89+273) K = 362 K
Substitute these values into equation 2
V₂ = (5×362)238
V₂ = 1810/238
V₂ = 7.61 liters
Which of the following will form a metallic bond with a metal?
a
another metal
b
none of the other choices
c
semimetal
d
a nonmetal
what is modal class?
தமிழ் வாழ்க
Answer:
Modal means the one that occurs most often (averages: mode). In maths, the mode is one of the most common ways to describe a set of data. ... The modal class is, therefore, the group with the highest frequency.
Answer:
Modal means the one that occurs most often (averages: mode). In maths, the mode is one of the most common ways to describe a set of data. ... The modal class is, therefore, the group with the highest frequency. For example: if you counted the number of pencils in different pencil cases and you decided to group them.
Explanation:
தமிழன் ❤
When the equation H202 + H2O + O2 is completely balanced, the SUM of all the coefficients will be
A.5
B. 8
C.3
D.4
How can the strength of an acid be determined using titration? (100 POINTS!)
Answer:
Explanation:
A titration in general is used to determine the concentration of something with a solution of known solution. For acid, a base solution of known concentration is added slowly. The end-point is determined by using a pH indicator. When the acid is neutralized at the end, note the amount of base solution used and the strength of acid can be calculated.
Note that the quantity of base solution utilised and the acid strength can be estimated after the acid has been neutralised.
What is titration?Titration is a method of chemical analysis where the quantity of a sample's constituents is established by adding a precisely measured amount of something else with which the component that is wanted will react in a specific, known proportion.
A burette, which is essentially a long, graded measurement tube with a stopper and a tube for injection at its bottom end, is used to gradually administer a standard solution of titrating reagent, and titrant, to a specified concentration. When the point of equal value is achieved, the addition is terminated. Note that the quantity of base solution utilised and the acid strength can be estimated after the acid has been neutralised.
Therefore, note that the quantity of base solution utilised and the acid strength can be estimated after the acid has been neutralised.
To know more about titration, here:
https://brainly.com/question/24704707
#SPJ2
We can predict that summer will follow spring. T or F
Answer:
T
Explanation:
Can I have someone to talk to it’s really important and I need advice..
Answer:
go for it
Explanation:
Answer:
I would be happy to help
Explanation:
Use the balanced equation from #13 to answer the following:
Calculate how many moles of SO2 can be produced with when given 75 grams of CS2.
Now calculate how many moles of SO2 can be produced with when given 96 grams of O2.
Which one is the limiting reactant (75 grams of CS2 or 96 grams of O2)? How do you know?
Answer:
1. 9600 moles
2. 4096 moles
Explanation:
CS2 + 3 O2=> CO2 + 2 SO2
1. The ratio for CS2: SO2 is :
1:2
If there are 75g of CS2 then there are:
75 × 2= 150g of SO2
Moles = mass × Mr
Moles = 150 × 64
Moles = 9600
2. The ratio for O2 : SO2 is:
3:2
If there are 96g of O2 then there are:
96 × 2/3 = 64g of SO2
moles = mass × Mr
Moles = 64 × 64
Moles = 4096
Answer: The FitnessGram PACER Test is a multistage aerobic capacity test that progressively gets more difficult as it continues. The test is used to measure a student's aerobic capacity as part of the FitnessGram assessment. Students run back and forth as many times as they can, each lap signaled by a beep sound.
Explanation:
A3.00 mol sample of CO2 (g) is in a rigid 6.00 L container at 400.°C.
Which of the following is the pressure of the gas?
16.4 atm
27.6 atm
200. atm
995 atm
Answer:
i'm thinking 27.6 not sure
Explanation:
What quantity of copper is deposited by the same quantity of electricity that deposited 9g of aluminum
Answer:
Mass of copper deposited = 31.75 g
Explanation:
According to Faraday's second law of electrolysis, when the same quantity of electricity is passed through different electrolytes, the relative number of moles of the elements deposited are inversely proportional to the charges on the ions of the elements.
From this law, it can be seen that the higher the charge, the lower the number of moles of a given element deposited.
Number of moles of aluminium in 9 g of aluminium = mass / molar mass
Molar mass of aluminium = 27 g
Number of moles of aluminium = 9/27 = 1/3 moles
Charge on aluminium ion = +3
3 moles of electrons will discharge 1 mole of aluminium,
1 mole of electrons will discharge 1/3 moles of aluminium
Number of moles of electrons involved = 1 mole of electrons
Charge on copper ion = +2
1 mole of electrons will discharge 1/2 moles of copper.
Mass of 1/2 moles of copper = number of moles × molar mass of copper
Molar mass of copper = 63.5 g
Mass of copper deposited = 1/2 × 63.5 = 31.75 g
State one type of additional information that could be used to determine if these three species are closely related.
Answer:
Study the bone structure of limbs.
Explanation:
Study the bone structure of limbs can be used to find out the relatedness and relationship among three species because the pattern of bones structure is similar but the structure is different from one another due to different environmental conditions. This study provides important and useful information whether the three species are closely related or not. If they have similar bone structure than we can say that there are more chances that they are closely related to each other.
How do plants and animals rely on each other?
Answer:
b
Explanation:
No links.
Calculate the pH and pOH of each solution.
a) [H + ] = 1.7 x 10 -8M
b) [H + ] = 1.0 x 10 -7M
Explanation:
first find the value of Ph
from Ph= -log[H+]
ph=-log[1.7x10^-8]=7.769
find Poh from 14=ph+poh
14=7.769+poh
Poh=6.231 part a
for part b the same as part a from the above procedure
How many moles of O₂ are needed to burn 2.5 moles of CH₃OH?
Answer:
3.75 moles
Explanation:
The chemical equation is 2CH₃OH + 3O₂ -> 2CO₂ + 4H₂O
2 moles of CH₃OH are burned by 3 moles of O₂
For 2.5 moles of CH₃OH are burned by x moles of O₂
Let's solve for x :
2*x=2.5*3 => 2*x=7.5 => x=3.75 moles of O₂ are needed to burn 2.5 moles of CH₃OH
In any engineering design problem, the first step is to understand the problem and identify one or more possible solutions. In this task, you’ll analyze the problems you face as the chemical engineer challenged with setting up the ammonia-making process. Recall the chemical equation for producing ammonia:
N2 + 3H2 ⇌ 2NH3 + energy
2.How can you change the chemical equilibrium to benefit the company? What benefits will be realized?
Answer:
Explanation:
2NH3(g)(→ N2(g)(+(3H2(g)
Eventually, these two reactions occur at the same rate. When this happens,
the concentrations of nitrogen, hydrogen, and ammonia become constant, and the
system is said to be “at equilibrium”. Typically,
we represent chemical equilibrium
using a double-headed reaction arrow:
TRUE OR FALSE
Astronomers use spectroscopes to identify elements in stars because each element produces
unique emission spectrum
Answer:
True!
Explanation:
A spectrum is simply a chart or a graph that shows the intensity of light being emitted over a range of energies. Have you ever seen a spectrum before? Probably. Nature makes beautiful ones we call rainbows. Sunlight sent through raindrops is spread out to display its various colors (the different colors are just the way our eyes perceive radiation with slightly different energies).
Hope i helped!
the process shown was used by Mendel during his experiments. What is the process called?
Answer: cross-pollination
Explanation:
How many atoms of carbon are in diamond
Answer:
A diamond contains 5.0 x 10 21 atoms of carbon.
Please help. I need help with all 4
What is happening when an oxygen molecule is formed from two separate oxygen atoms?
someone pls answer i will in fact give u brainliest
Answer:
d. Solid
Explanation:
It is frozen to be a glacier
Hope this helps :)
Rubidium Rb
when was the element discovered and by whom ??? ASAP MAKE IT AT LEAST A PARAGRAPH!!!
Answer:
Rubidium Rb was discovered in 1861It was discovered by the German chemist Robert Wilhelm Bunsen and the German physicist Gustav-Robert KirchoffExplanation:
Rubidium was discovered by the German chemists Robert Bunsen and Gustav Kirchhoff in 1861 while analyzing samples of the mineral lepidolite with a device called a spectroscope. The sample produced a set of deep red spectral lines they had never seen before. Bunsen was eventually able to isolate samples of rubidium metal. Today, most rubidium is obtained as a byproduct of refining lithium.
Which action could a student take to produce a longitudinal wave with a large amplitude
Answer:
bang on a drum
Explanation:
Answer:
Bang on drum
Explanation:
Its right.
PLEASE HELP AND FAST!! How many grams of NH4OH are in 0.125L of a 1.4 M solution of NH4OH?
Answer:
6.132
Explanation:
An aerosol can contains gases under a pressure
of 4.4 atm at 26 ◦C. If the can is left on a
hot sandy beach, the pressure of the gases
increases to 4.68 atm. What is the Celsius
temperature on the beach?
Answer in units of ◦C.
Answer:
e
Explanation:
and e
The velocity of an object consists of its speed and..
A. Average speed
B. Distance
C. Displacement
D. Direction
Answer:
direction
Explanation:
When balancing chemical equations, it is okay to adjust
(3 points)
A.
coefficients.
B.
superscripts.
C.
subscripts.
D.
any of these.
Answer:
A
Explanation:
Thats the correct anwers
please help me do it dont worry the answers are their just put them in theright place