Answer:
31.98g/mol
Explanation:
Using Graham's law of diffusion, which states that the rate of diffusion of a gas is inversely proportional to the square root of its molecular mass (M). Rate of diffusion = volume/time.
Since both gas S and Q have equal volumes, we can calculate molecular mass of gas Q as follows:
tQ/tS = √mQ /√mS
Where:
tQ = time of diffusion of gas Q
tS = time of diffusion for gas S
mQ = molar mass of gas Q
mS = molar mass of gas S
According to the information provided in this question;
tQ = 240s
tS = 180s
mQ = ?
mS = 18g/mol
Using tQ/tS = √mQ /√mS
240/180 = √mQ / √18
1.333 = √mQ / √18
Square both sides
1.333² = mQ/18
1.78 = mQ/18
mQ = 18 × 1.78
mQ = 31.98g/mol
Molar mass of Q = 31.98g/mol
calculate the speed of a train that travels 540 km in 9 hours
Answer:
s=d/t. d=540 t=9h
540÷90=6 km/h
For the balanced equation shown below, how many grams of CO2 will be
produced from 74.23 grams of CO? CO + Fe3O4 → 3FeO + CO2
Answer:
116.64 g
Explanation:
74.23÷14 This is # of moles .
# of moles for co = 5.302
Then mass of co2 = 116.64
during hybridization ______.
A) nature selects which organisms will survive and reproduce.
B) the nucleus of a cell is removed.
C) two organisms with desired traits are bred.
D) a single beneficial trait is bred into a species.
Answer:
option C two organisms with desired traits are bred
Which of the following could be classified as producing a physical change?
A. Burning a candle
B. Leaving a bicycle outside to rust
C. Bending sheet metal
D. Toasting a slice of bread
Answer:
C. Bending sheet metal.
Explanation:
The metal is still intact. No change in chemical bonds have occurred.
Burning a candle is converting wax into heat, CO2 and carbon soot.
A rusting bicycle is converting goof iron, Fe, into iron oxide (rust, Fe2O3)
Toasting bread is more difficult to define. If the bread is just warmed, then it is physical. If it is toasted (browned/burned), then a few surface molecules have been converted into tasty carcinogens, my favorite poison.
URGENT PLEASE HELP
What most likely happens when a sodium atom comes near an atom having seven valence electrons?
Answer:
7 Electrons
Explanation:
What it is fill its valence shell, it would need to acquire 7 electrons - a difficult task for a metal like sodium that is a known electron-loser. So unlike fluorine and oxygen, sodium acquires a full octet by losing electrons and emptying out its outermost shell.
A chemist dilutes a 1. 0 mL sample of 2. 0 M KNO3 by adding water to it. If the concentration of the solution that is obtained is 0. 0080 M, what is its volume? Use M subscript i V subscript i equals M subscript f V subscript f. 125 mL 250 mL 500 mL 2,000 mL.
Answer:
We know the initial volume of the potassium nitrate solution is 1.0 mL and the initial concentration is 2.0 M, we also know that an unknown volume of water was added to the solution, which diluted our concentration down to a final value of 0.008 M. We are trying to find the final volume.
Here we can use this formula since the initial and final solutions are proportional. Before that let's define our variables.
[tex]M_1 = 2.0 M\\V_1 = \frac{1.0 mL}{1000} = 0.001 L\\M_2 = 0.008 M\\V_2 = \ ?[/tex]
[tex]M_{1}V_{1} =M_2 V_2\\[/tex]
[tex](2.0)(0.001) = (0.008)V_2\\\\\frac{(2.0)(0.001)}{0.008} = V_2\\\\V_2 = 0.25 L \ or \ (0.25 \ * \ 1000) = 250 \ mL[/tex]
Therefore you would have 0.25 L or 250 mL of your final solution.
Is it unbalanced or balanced if hydrogen reacts to iodine?
Answer:
unbalanced
Explanation:
because it is REACTing.
Which of the following methods will usually cause a reaction to speed up?
Group of answer choices
Removing the catalyst.
Combining the reactants at a lower temperature.
Grinding one of the reactants into a powder.
Reducing the concentration of reactants.
the method that will usually cause a reaction to speed up from the list given is: Reducing the concentration of reactants.
Meaning of ReactionReaction can be defined as the combination of substances or a process where substances acts on each other, where substances changes into different substances.
A reaction can be said to be the event that causes a restructuring or rearrangement of atoms of a substance when it is in contact with another substance.
In conclusion, the method that will usually cause a reaction to speed up from the list given is Reducing the concentration of reactants.
Learn more about Reaction: https://brainly.com/question/26018275
#SPJ2
A substance that takes the shape and volume of its container is in this phase is called a liquid
Answer:
liquid matter
Explanation:
How to get your crush to like you back
What type of mixture is throughly mixing powdered lemonade with water
Answer:
I believe it would be a solution I could be wrong tho
Explanation:
Answer:
a solution
Homogeneous mixtures (solutions)
Explanation:
Lemonade is a special type of mixture called a solution.
...................................................................................................................................................
What type of mixture is made by thoroughly mixing powdered lemonade with water?
Homogeneous mixtures (solutions)
Mixtures with substances dissolved evenly into one another, like pink lemonade powder dissolved in water, are called homogeneous mixtures, or solutions.
A sealed flask initially contains pure nitrogen dioxide gas (NO,). Over time, the nitrogen dioxide forms dinitrogen tetroxide gas (N,O.). The graph below shows the relative amounts of (NO,) and (N20.) over time. What is true about the time indicated by the blue arrow?
This problem is providing information about the equilibrium reaction whereby nitrogen dioxide gas produced dinitrogen tetroxide gas as shown on the attached picture and the following chemical equation:
NO₂ (g) ⇄ N₂O₄ (g)
In such a way, we can consider the given choices to reason the following: the blue arrow is pointing out the arrival to the equilibrium condition for the reaction, a point in which the rate of the forward reaction (formation of N₂O₄) is equal to the rate of the reverse reaction (formation of NO₂), because the molecules will fluctuate to the same relative amounts defined by the equilibrium constant.
Therefore the answer will be the first one on the attached file, which can vary on your online homework format.
It is important to note that the reactant is not used up at any point of the graph (concentration drops to 0) and also, the activation energy cannot be analyzed with this sparse information.
Learn more:
(equilibrium concentrations) https://brainly.com/question/7949757How do you break down an element?
Answer:
elements cannot be break downHellpppppppppppppppppppppp
Answer:
SnH4
Explanation:
Because the melting point of SnH4 is higher than CH4
what makes matter change from one state to another?
Answer: Adding or removing energy from matter
Explanation:
what is the difference between hypertonic and hypotonic
A force is a push or a pull under the right circumstances anything can exert a force push a notebook or some other object so that it slides across a table or desktop what force causes the notebook to start moving what force causes the notebook to stop moving?
Answer:
the force that you applied caused the notebook to move.the force applied on the notebook by the table causes it to stop moving. this is because after sometime the book uses up the force and later the force you applied is less than that of the force by the table.
Why are metals sometimes added to gold?
to make it softer and more malleable
to improve the value of gold
to raise its melting point
to make gold stronger and more durable
How does a paper bag wrapped around a hot water bottle create convection?
A chemist heats a gas within a sealed, rigid container. Which statement describes the changes that occur in the gas? (1 point)
-The gas particles move slower and hit the sides of the container with less force, consequently, the pressure
increases
-The gas particles move slower and hit the sides of the container with less force, consequently, the pressure decreases
-The gas particles move faster and hit the sides of the container with more force, consequently, the pressure
increases
-The gas particles move faster and hit the sides of the container with more force, consequently, the pressure
decreases
When a gas is heated in a sealed container, the gas particles move faster and hit the sides of the container with more force leading to an increase in the pressure of the gas.
An increase in the temperature of a gas increases the collision rate of the molecules of the gas according to the kinetic theory.
With increased kinetic energy, the molecules of the gases collide more frequently with each other and the walls of the container.
The collision creates an increase in the magnitude of pressure inside the container.
More on the kinetic theory of gases can be found here: https://brainly.com/question/15354399?referrer=searchResults
Answer:
C
Explanation:
When a gas is heated in a sealed container, the gas particles move faster and hit the sides of the container with more force leading to an increase in the pressure of the gas.
calculate the molarity of a 50.0 ml of a 0.150 m hcl solution when 30.0 ml of water is added.
Answer:
0.09375 M
Explanation:
You want to use the following equation:
M1*V1=M2*V2
Then plug in the 50ml to V1 and 0.15M to M1 and 80ml to V2 (add the 50 and 30). The next thing you want to do is change the mL to liters, since Molarity is moles/liter. Once that is done, solve algebraically for answer.
** Also don't forget to capitalize the M when you mean Molarity, because it is different than m.**
Hope this helps!
Please help me with this three questions
Answer:
1. A. Thyroid Gland Function
B. detecting Blood Clots
C. Treating Cancer
2. An example would be how many are used as tracers for diagnostic purposes
3. Beneficial because it gives us ways to eleminate pests, by the sterile insect technique
Number three is kinda iffy a bit difficult to explain it may be explained better in your book.
using the two ways you have learned about between temperature, pressure and volume, what are two ways you could increase the gas pressure of a system.
Answer:
I don't know do you know tell me please
what mass does a nuetron have?
Answer:
1 AMU
Explanation:
Protons, neutrons, and electrons: Both protons and neutrons have a mass of 1 amu and are found in the nucleus.
Based on the graph, what is the approximate half-life of the reaction shown below
Answer: 2.1 minutes
Explanation: Based on the graph, what is the approximate half-life of the reaction shown below
What is the molarity of a 75.0 mL solution that contains 0.225 g of
potassium nitrate?
Answer:
M=0.0297M
Explanation:
we know that molarity equals number of mole of solute over the volume of solution.
M=n/V but n=m/M
n=0.225g÷101g/mol =0.00223mol
M=0.00223mol/0.075l
M=0.0297M
Answer:
0.0297M
Explanation:
We will use the formula M= moles of solute/lites of solution.
First we need to figure out the Moles of the solute, to get this we first need the molar mass of KNO3 (potassimum nitrate).
The Molar Mass of potassimum nitrate is 101.103 g/mol
K - 1 x 39.09
N - 1 x 14.006
O - 3 x 15.999
KNO3 - 101.103 g/mol
Now we get the moles of the solute by doing.
0225g/ 101.103g/mol = 0.00223 mol
Put the answer into the orginal equation to get 0.00223mol / 0.045 L
Which equals to 0.0297M. This is also the correct amount of significant figures.
Help. 50 points. Need honest answers.
Answer:
ok
Explanation:
Elements are usually dull, brittle and do not conduct electricity are know as_____.
Points: 46
Answer:
nonmetals. it's one of them
Note the mass of copper(1) oxide formula unit 143.091 what is the mass of 8.250 moles of Cu2O
Answer:
The mass of 8.250 moles of Cu2O is 1180.5g
Explanation:
HOW TO CALCULATE MASS OF A SUBSTANCE:
The mass of a substance can be calculated by multiplying the number of moles in the substance by its molar mass as follows:Mass (g) = no. of moles (mol) × molar mass (g/mol)
Molar mass of copper (I) oxide (Cu2O) = 63.5(2) + 16 = 143.09 g/molMass of Cu2O = 8.250 mol × 143.09 g/mol
Mass of Cu2O = 1180.5 g
Therefore, the mass of 8.250 moles of Cu2O is 1180.5 g.
Mr. Green gave his students a set of items.
They had a toothpick, pencil, paper clip, safety pin, nail, and dime. He also gave them a magnet. He told them to predict which items are magnetic.
How can they test their predictions?
A.
weigh each of the items
B.
see which items stick to the pencil
C.
measure each of the items
D.
see which items stick to the magnet
Answer:
D. see which items stick to the magnet
Explanation:
To predict which items are magnetic, the students will have to test whether or not each item is attracted to the magnet. Only objects that are magnetic stick to a magnet, so all of the items that stick to the magnet should be magnetic.
Hopefully that's helpful! :)
