Three mixtures were prepared from three very narrow molar mass distribution polystyrene samples with molar masses of 10,000, 30,000 and 100,000 g mol−1 as indicated below: (a) Equal numbers of molecules of each sample (b) Equal masses of each sample (c) By mixing in the mass ratio 0.145:0.855 the two samples with molar masses of 10,000 and 100,000 g mol−1 For each of the mixtures, calculate the number-average and weight-average molar masses and comment upon the meaning of the values.
Answer:
(a). 46,666.7 g/mol; 78,571.4 g/mol
(b). 86950g/mol; 46,666.7 g/mol.
(c). 86950g/mol; 43,333.33 g/mol
Explanation:
So, we are given the molar masses for the three samples as: 10,000, 30,000 and 100,000 g mol−1.
Thus, the equal number of molecule in each sample = ( 10,000 + 30,000 + 100,000 ) / 3 = 46,666.7 g/mol.
The average molar mass = [ ( 10,000)^2 + (30,000)^2 + 100,000)^2] ÷ 10,000 + 30,000 + 100,000 = 78,571. 4 g/mol.
(b). The equal masses of each sample = 3/[ ( 1/ 10,000) + (1/30,000 ) + (1/100,000) ] = 20930.23 g/mol.
Average molar mass = ( 10,000 + 30,000 + 100,000 ) / 3 = 46,666.7 g/mol.
(c). Equal masses of the two samples = (0.145 × 10,000) + (0.855 × 100,000)/ 0.145 + 0.855 = 86950g/mol.
The weight average molar mass = 1.7 + 10,000 + 100,000/ 1.7 + 1 = 43,333.33 g/mol.
Use the drop-down menus to label the graph
according to its type.
Answer:
relation (but not a function)
Explanation:
c on edge
How many atoms are in 4.5 moles of nitrogen
Answer:one mole of stuff (atoms, molecules, eggses), there are NA individual items of that stuff. So, there are 4.5 × NA BCl3 molecules; i.e. 4.5 × 6.022×1023 ≅ 27×1023 individual molecules of BCl3
Explanation:
Answer:
[tex]\boxed {\boxed {\sf About \ 2.7 *10^{24}\ atoms\ N }}[/tex]
Explanation:
To convert from moles to atoms, Avogadro's Number: 6.022*10²³ must be used. This number tells us the amount of particles (atoms, molecules, etc) in 1 mole of a substance. In this case, the particles are atoms of nitrogen.
[tex]\frac {6.022 *10^{23} \ atoms \ N}{1 \ mol \ N}[/tex]
Multiply by the given number of moles: 4.5
[tex]4.5 \ mol \ N *\frac {6.022 *10^{23} \ atoms \ N}{1 \ mol \ N}[/tex]
The moles of nitrogen will cancel.
[tex]4.5 \ *\frac {6.022 *10^{23} \ atoms \ N}{1 }[/tex]
The denominator of 1 can be ignored.
[tex]4.5 \ *{6.022 *10^{23} \ atoms \ N}[/tex]
[tex]2.7099*10^{24} \ atoms \ N[/tex]
The original measurement of moles had 2 significant figures, so our answer must have the same. For the number we calculated, that is the tenth place. The 0 in the hundredth place tells us to leave the 7.
[tex]2.7 *10^{24}\ atoms\ N[/tex]
There are about 2.7*10²⁴ atoms of nitrogen in 4.5 moles.
Can some one help I'm lost iam being timed:( Show using two conversion factors how you would convert from 0.020 kg into mg
Answer:
2.0 × 10⁴ mg
Explanation:
Step 1: Given data
Mass (m): 0.020 kg
Step 2: Convert the mass from kilograms to grams
We will use the conversion factor 1 kg = 1,000 g.
0.020 kg × (1,000 g/1 kg) = 20 g
0.020 kg is equal to 20 g.
Step 3: Convert the mass from grams to milligrams
We will use the conversion factor 1 g = 1,000 mg.
20 g × (1,000 mg/1 g) = 2.0 × 10⁴ mg
20 g is equal to 2.0 × 10⁴ mg. Then, 0.020 kg is equal to 2.0 × 10⁴ mg.
____ Al + ____ Cr2O3 ____ Al2O3 + ____ Cr
If the reaction of 23.3 grams of Cr2O3 produces 5.35 grams
of Al2O3, what is the percent yield?
Answer:
[tex]Y=34.3\%[/tex]
Explanation:
Hello there!
In this case, according to the balanced chemical reaction:
[tex]2Al + Cr_2O_3 \rightarrow Al_2O_3 + 2Cr[/tex]
We notice there is a 1:1 mole ratio between Al2O3 and Cr2O3; thus, the following stoichiometric setup is used to compute the theoretical yield first:
[tex]m_{Al_2O_3 }=23.3gCr_2O_3*\frac{1molCr_2O_3}{151.99gCr_2O_3} *\frac{1molAl_2O_3}{1molCr_2O_3} *\frac{101.96gAl_2O_3}{1molAl_2O_3} \\\\m_{Al_2O_3}=15.6gAl_2O_3[/tex]
Thus, the percent yield turns out:
[tex]Y=\frac{5.35g}{15.6g} *100\%\\\\Y=34.3\%[/tex]
Best regards!
How many grams are in 2.49 x 10^24 atoms of Hg?
Answer:
[tex]m_{Hg}=829.4gHg[/tex]
Explanation:
Hello there!
In this case, considering the Avogadro's number, which helps us to realize that 1 mole of mercury atoms contains 6.022x10²³ atoms and at the same time 1 mole of mercury weights 200.59 g, we obtain:
[tex]m_{Hg}=2.49x10^{24}atoms*\frac{1mol}{6.022x10^{23}atoms} *\frac{200.59g}{1molHg}\\\\m_{Hg}=829.4gHg[/tex]
Best regards!
The hydronium ion concentration of an aqueous solution of 0.502 M pyridine (a weak base with the formula C5H5N) is
Answer:
1.99×10¯¹⁴ M
Explanation:
We'll begin by writing the balanced dissociation equation of pyridine. This is illustrated below:
C₅H₅N + H₂O <=> C₅H₆N⁺ + OH¯
From the balanced equation above,
1 mole of C₅H₅N produced 1 mole of OH¯.
Therefore, 0.502 M C₅H₅N will also produce 0.502 M OH¯.
Finally, we shall determine the concentration of hydronium ion, H₃O⁺ in the solution. This can be obtained as follow:
Concentration of Hydroxide ion [OH¯] = 0.502 M
Concentration of hydronium ion [H₃O⁺] =?
[H₃O⁺] [OH¯] = 1×10¯¹⁴
[H₃O⁺] × 0.502 = 1×10¯¹⁴
Divide both side by 0.502
[H₃O⁺] = 1×10¯¹⁴ / 0.502
[H₃O⁺] = 1.99×10¯¹⁴ M
Thus, the concentration of hydronium ion, H₃O⁺ in the solution 1.99×10¯¹⁴ M
write the balanced chemical equation for lab preparation of oxygen gas by using heat
Answer:
O + O ---Δ----> O2
Explanation:
plz follow me friend
Answer:
hello my ne is yash follow me please
The most prominent feature of ocean topography discovered in the 1960s was:
a mountain ridge which circles the earth
subduction zones
volcanic activity at the ocean bottom
seamounts
answer:
a mountain ridge which circles the earth
subduction zones
in coca cola the ingridents are : CARBONATED WATER.
HIGH FRUCTOSE CORN SYRUP.
CARAMEL COLOR.
PHOSPHORIC ACID.
NATURAL FLAVORS.
CAFFEINE. my question is that is the caffienne turning it black or the carmel coler
Answer:
Coca-Cola (and other Colas) are dark because food colouring is added to the mixture (caramel colour) to create the traditional colour of colas.
Today we still colour our colas this way, because of tradition: That is the colour colas are supposed to be.
Explanation:
Help me please omg
Answer the following question:
How many moles of ammonia are in 375. mL of a 2.25 M aqueous ammonia solution?
Find the numerical answer for this question and make sure to include the following:
What is the chemical formula for ammonia?
What is the formula for molarity?
When you give your numerical answer, what is the correct significant figures and how do you know that is the correct amount?
Answer:
NH₃
M = n/V(L)
0.844 mol (Both numbers have 3 significant figures so the result has 3 significant figures as well)
Explanation:
Step 1: Given and required data
Volume of solution (V): 375. mLMolar concentration of the solution (M): 2.25 MChemical formula for ammonia: NH₃Step 2: Calculate the moles (n) of ammonia (solute)
Molarity is equal to the moles of solute divided by the liters of solution.
M = n/V(L)
n = M × V(L)
n = 2.25 mol/L × 0.375 L = 0.844 mol (Both numbers have 3 significant figures so the result has 3 significant figures as well)
What is the oxidation number of bromine in the BrO3- ion?
Two experiments were conducted: 4.125 g of copper(II) oxide, CuO2, was reduced by heating at high pressure with excess hydrogen to yield 3.294 g of copper Cu. 1.179 g of copper Cu was dissolved in nitric acid to yield copper(II) nitrate, which was converted to 1.476 g copper(II) oxide, CuO2, on ignition. Show that the results illustrate the law of definite proportions by calculating the percentage of oxygen in copper(II) oxide in experiments 1 and 2.
Answer:
Explanation:
4.125 g of copper oxide contains 3.294 g of Cu . Rest is oxygen
oxygen is 4.125 - 3.294 = .831 g
Ratio of oxygen and copper = .831 : 3.294
.831 / .831 : 3.294 / .831
= 1 : 3.96
1 : 4 ( Approx )
percentage of oxygen in copper oxide = 20 % approx
in the second experiment ,
1.476 g of copper oxide is formed from 1.179 g of Cu
oxygen in this copper oxide = 1.476 - 1.179 = .297 g
Ratio of oxygen and copper
.297 : 1.179
.297/.297 : 1.179/ .297
1 : 3.96
1 : 4 ( approx )
percentage of oxygen in copper oxide = 20 % approx
So it follows the law of definite proportions .
Draw the structure of the major organic product(s) for the following reaction between an acetylenic anion and an alkyl halide. (The reaction stoichiometry is 1:1.) A carbon carbon triple bond where carbon 1 is a carbanion with a lone pair and carbon 2 is bonded to methyl. This reacts with a 5 carbon chain where carbon 3 has a bromine substituent.
Answer:
See explanation below
Explanation:
In this case, we are having a reaction between an anion and alkyl halide. The carbon 1 of the anion will act as nucleophile and will attack the electrophile, which is 5 carbon chain with the bromine in the third carbon.
Now, the nucleophyle is an alkyne of 3 carbon. According to the description, it should be:
CH₃ - C ≡ C⁻
And the alkyl halide is:
CH₃ - CH₂ CH(Br) - CH₂ - CH₃
And the final product after the reaction would be the following:
CH₃ - C ≡ C - CH - (CH₂CH₃)₂
However, in the attached picture you can see this better and the mechanism of reaction.
Hope this helps
which has more gravity
A. Earth
B. Sun
C. Saturn
B
the sun!
yay
!!!!!!!!!!!
Answer:
EARTH
Explanation:
Earth‘s gravity, as already noted, is equivalent to 9.80665 m/s² (or 32.174 ft/s²). This means that an object, if held above the ground and let go, will accelerate towards the surface at a speed of about 9.8 meters for every second of free fall.
5. If the reaction of carbon monoxide and oxygen gas in question 2
produced 7.03E24 molecules of CO2, what is the mass in grams? Use
44g/mol for M.M. of CO2 and round your answer to the nearest whole
number. *
Answer: The mass in grams is 514.8.
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to molecular mass and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
To calculate the number of moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given molecules}}{\text{Avogadros number}}[/tex]
given molecules = [tex]7.03\times 10^{24}[/tex]
Putting in the values we get:
[tex]\text{Number of moles}=\frac{7.03\times 10^{24}}{6.023\times 10^{23}}=11.7moles[/tex]
mass of [tex]CO_2=moles\times {\text {Molar mass}}=11.7mol\times 44g/mol=514.8g[/tex]
The mass in grams is 514.8.
Ge(NO2)2 whats the name of this formula?
Answer:
Germanium monoxide
hope this helps :)
2 Cu + Cl2 ----> 2 Cuci
If 1.64 moles of chlorine is reacted with 3.23 moles of copper, how many grams of copper I chloride will be made?
(The next question will ask about the limiting and excess reactants for this reaction)
o 320 g
O 160 g
O 162 g
O 325 g
Answer:
320 g.
Explanation:
Hello!
In this case, according to the balanced chemical reaction, we can compute the grams of copper I chloride produced by each reactant, as shown below:
[tex]m_{CuCl}^{by\ Cu}=3.23molCu*\frac{2molCuCl}{2molCu}*\frac{99.0gCuCl}{1molCuCl} =320gCuCl\\\\m_{CuCl}^{by\ Cl_2}=1.64molCl_2*\frac{2molCuCl}{1molCl_2}*\frac{99.0gCuCl}{1molCuCl} =325gCuCl[/tex]
Thus, since copper produces the fewest grams of CuCl, we infer it is the limiting reactant, therefore the correct mass of copper I chloride is 320 g.
Best regards!
Hydrogen gas is a product of the reaction of
magnesium with hydrochloric acid. How many
liters of hydrogen gas are produced from the
complete reaction of 146.5 g magnesium metal at
2.40 atm and a temperature of 314 K?
(Mg = 24.30 g/mol)
Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)
Hint: R = 0.0821 L atm/(mol K)
Answer:
64.7
Explanation:
Answer:
64.7 is the answer
hope this helps
have a good day :)
Explanation:
The irreversible elementary gas-phase reaction is carried out isothermally at 305 K in a packed-bed reactor with 100 kg of catalyst. The entering pressure was 20 atm and the exit pressure is 2 atm. The feed is equal molar in A and B and the flow is in the turbulent flow regime, with FA0 10 mol/min and CA0 0.4 mol/dm3. Currently 80% conversion is achieved. What would be the conversion
Answer:
0.856.
Explanation:
Lets represent the irreversible elementary gas phase equation of reaction as
A + B -----------------------------------> C + D
We have that the percentage of conversion is 80%.
The pressure, p from the ratio of exit pressure and entering pressure is p = 2/20 = 1/10 = 0.1.
Therefore, n = 1 - p^2/ weight of the catalyst = 1 - 0.1^2/ 100 = 9.9 × 10^-3 kg cat^-.
Now, let's make use of the equation below;
J/ 1 - J = kb^2/ u [ w - nw^2/2] ----------(1).
0.8 / 1- 0.8 = k ( 0.4)^2/ 10 [ 100 - (9.9× 10^-3 × 100^2/ 2] .
k = 4.95 dm^6/ kg.cat .mol.min
The turbulent flow= 1/2 × 9.9 × 10^-3 = 4.95 × 10^-3 kg cat^-.
Thus, making use of the equation (1) again, we have that;
{4.95 × 10^-3 × 0.4}/ 10 × [ 100 - (4.95 × 10^-3 × 100^2)] / 2 = 5.964.
Therefore, a/1 - a = 5.964.
5.964( 1 - a) = a.
5.964 - 5.964a = a.
5.964 = a + 5.964a.
5.964 = 6.964a.
a = 5.964/ 6.964 = 0.856.
(trying this again because this test is due at 3 and paimon has to get this done or she will fail!! paimon will try to give brainlist if brainly lets her!!)
The _________________molecules in the food we eat are_____________.
A. Enzyme, water
B. Small, insoluble
C. Large, insoluble
D. Enzyme, insoluble
How many grams are there in a 3.5 moles of oxygen
Answer:
112 of O2
Explanation:
Now if simply oxygen is given so we'll consider O2
3.5 moles O2 means,
3.5 x 32 = 112 grams of O2
Considering the definition of molar mass, the mass of 3.5 moles of O₂ is 112 grams.
Definition of molar massThe molar mass of substance is a property defined as its mass per unit quantity of substance, in other words, molar mass is the amount of mass that a substance contains in one mole.
The molar mass of a compound (also called Mass or Molecular Weight) is the sum of the molar mass of the elements that form it (whose value is found in the periodic table) multiplied by the number of times they appear in the compound.
Molar mass of O₂In this case, you know the molar mass of the oxygen O is 16 g/mole.
So, the molar mass of the compound O₂ is calculated as:
O₂= 2× 16 g/mole
Solving:
O₂= 32 g/mole
Mass of 3.5 moles of O₂Next, you can apply the following rule of three: If by definition of molar mass 1 mole of the compound contains 32 grams, 3.5 moles of the compound contains how much mass?
[tex]mass= \frac{3.5 molesx32 grams}{1 mole}[/tex]
mass= 112 grams
Finally, the mass of 3.5 moles of O₂ is 112 grams.
Learn more about molar mass:
brainly.com/question/5216907
brainly.com/question/11209783
brainly.com/question/7132033
brainly.com/question/17249726
#SPJ2
Which of Newton's Three Laws is BEST described by the following statement: A ball dropped from the 10th story of a hotel had more force than when the same ball was dropped from the 5th story of the same hotel
Answer:
I believe the answer is Newton's Second Law
Explanation:
Newton's Second Law states that the acceleration of an object will count on how much mass and the amount of force that is applied.
The bowling ball was dropped from the 10th story window and had more force than when the ball was dropped from the 5th story window because the 10th story window gave the bowling ball more acceleration.
Convert the volume, nm^3, to liters (L) by using the box dimensions of 4nm x 8.75nm x 10nm. Use the conversion factor of 1 L = 1 dm^3. Do not convert directly from nm^3 to dm^3
Answer:
[tex]V=3.50x10^{-22}L[/tex]
Explanation:
Hello there!
In this case, given the dimensions of the box, we first compute the volume by multiplying each side:
[tex]V=4nm*8.75nm*10nm=350nm^3[/tex]
Next, we apply the following conversion factor in order to obtain the corresponding liters:
[tex]V=350nm^3*(\frac{1m}{10^9nm} )^3*\frac{1000L}{1m^3} \\\\V=350nm^3*\frac{1m^3}{10^{27}nm^3} *\frac{1000L}{1m^3}\\\\V=3.50x10^{-22}L[/tex]
Best regards!
Given the following balanced chemical equation:
N2(g) + 3H2(g) + 2NH3(8)
What is the maximum amount of NH3(g) that can be produced from 2.0 mol H2(g)? Assume that N2(g) is the excess reactant.
Answer:
22 g
Explanation:
Step 1: Write the balanced equation
N₂(g) + 3 H₂(g) ⇒ 2 NH₃(g)
Step 2: Calculate the moles of NH₃ produced from 2.0 moles of H₂
The molar ratio of H₂ to NH₃ is 3:2.
2.0 mol H₂ × 2 mol NH₃/3 mol H₂ = 1.3 mol NH₃
Step 3: Calculate the mass corresponding to 1.3 moles of NH₃
The molar mass of NH₃ is 17.03 g/mol.
1.3 mol × 17.03 g/mol = 22 g
What happens to a linguist when it releases enough energy
Answer:
When a liquid releases enough energy, the liquid will freeze and turn into a solid. Phase changes are what causes one state of matter to turn into another. All phase changes are physical changes.
Explanation:
if ur really saying liquid a person accomplished in languages
especially : one who speaks several languages ?
please mark as brainliest
Please help me answer this question I need it before 12:59
Answer:
because the brian is like a computer because that both use electrical signals to send messages the brain uses chemicals to transmit information and the computer uses electricity.
Hope that was helpful
Why are watersheds important for the maintenance of water quality? Choose all that apply.
Select 2 correct answer(s)
Question 3 options:
they can transfer pollutants
their soil and plants can filter and clean water
they cause precipitation and acid rain
they cause floods
Answer:
its A and D
Explanation:
i took the quiz
Answer:
a and d
Explanation:
If you begin with 14.0g of TiCl4(1), how many liters of H2O(g) will need?
Answer:
3.32 L
Explanation:
Step 1: Write the balanced equation
TiCl₄(l) + 2 H₂O(g) → TiO₂(s) + 4 HCl(g)
Step 2: Calculate the moles corresponding to 14.0 g of TiCl₄
The molar mass of TiCl₄ is 189.68 g/mol.
14.0 g × 1 mol/189.68 g = 0.0738 mol
Step 3: Calculate the moles of H₂O needed to react with 0.0738 moles of TiCl₄
The molar ratio of TiCl₄ to H₂O is 1:2. The moles of H₂O needed are 2/1 × 0.0738 mol = 0.148 mol
Step 4: Calculate the volume corresponding to 0.148 moles of H₂O(g)
At standard temperature and pressure, 1 mole of H₂O(g) has a volume of 22.4 L.
0.148 mol × 22.4 L/1 mol = 3.32 L
short note on dung fertilization
Answer:
Most manure consists of animal feces; other sources include compost and green manure. Manures contribute to the fertility of soil by adding organic matter and nutrients, such as nitrogen, that are utilised by bacteria, fungi and other organisms in the soil.
Explanation:
Hope it is helpful....
Answer:
Animal manure, such as chicken manure and cow dung, has been used for centuries as a fertilizer for farming. It can improve the soil structure (aggregation) so that the soil holds more nutrients and water, and therefore becomes more fertile. ... Manure is also commercially composted and bagged and sold as a soil amendment.
Explanation: