Answer:
0.0013 moles
Explanation:
moles = volume/ molar volume of gas
=240/24000cm3 (convert dm3 to cm3)
=0.0013
does salt affect the boiling time of water?
Answer:
Yes
Explanation:
Yes, but almost insignificantly. The regular boiling point of water is 100 degrees celcius, adding a small handfull of salt will increase the boiling point to roughly 100.04 degrees celcius. Therefore, it is almost insignificant but still does affect it. This is mainly because salt changes the way the molecules react thus making it harder for them to change state from liquid to gas. This ultimately causes the water to get hotter before boiling actually occurs.
Why do need need pure substances
Answer:
To extract its derivatives without impurities
What happens to the freezing point of a solution when more solute is added?
Answer:
Explanation:
Freezing point depression is the phenomena that describes why adding a solute to a solvent results in the lowering of the freezing point of the solvent. Adding solute to a solvent will essentially dilute the solvent molecules
Answer:
The freezing point decreases
Why don’t scientists use the Bohr model above to explain charge transfer?
Answer:
nsksbsjensnsjeiejensbsksks
How much water can be produced when 18 grams of pentane is burned in air? C5H12 + 8 02 --> 5 CO2 + 6 H2O. 9.0 g 18 g 27 g 36 g 729
Answer: The mass of water produced is 27 g
Explanation:
The number of moles is defined as the ratio of the mass of a substance to its molar mass.
The equation used is:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)
Given mass of pentane = 18 g
Molar mass of pentane = 72.15 g/mol
Plugging values in equation 1:
[tex]\text{Moles of pentane}=\frac{18g}{72.15g/mol}=0.250 mol[/tex]
The given chemical equation follows:
[tex]C_5H_{12}+8O_2\rightarrow 5CO_2+6H_2O[/tex]
By the stoichiometry of the reaction:
If 1 mole of pentane produces 6 moles of water
So, 0.250 moles of pentane will produce = [tex]\frac{6}{1}\times 0.250=1.5mol[/tex] of water
Molar mass of water = 18 g/mol
Plugging values in equation 1:
[tex]\text{Mass of water}=(1.5mol\times 18g/mol)=27g[/tex]
Hence, the mass of water produced is 27 g
How many moles of oxygen are required to react with methanol in order to produce 13 moles of formaldehyde?
Answer:
6.5 moles of Oxygen are required
Explanation:
Based on the reaction:
CH3OH + 1/2 O2 → CH2O + H2O
1 mole of methanol reacts with 1/2 moles O2 to produce 1 mole of formaldehyde and 1 mole of water.
Thus, to produe 13 moles of formaldehyde, CH2O, are needed:
13 moles CH2O * (1/2mol O2 / 1mol CH2O) =
6.5 moles of Oxygen are requiredWhat do you notice about the distance between the terrestrial planets compared with the spacing between the gas giants
Answer:
The spacing between the terrestrial planets is less than that between the gas planets.
Explanation:
Since the terrestrial planets which are Mercury, Venus, Earth and Mars have a distance of 0.4 AU, 0.7 A.U, 1.0 AU and 1.5 A.U respectively from while the gas planets which are Jupiter, Saturn, Uranus and Neptune have a distance of 5.2 AU, 9.6 AU, 19.6 AU and 30 AU respectively from the sun, we can see that the spacing between the terrestrial planets is much smaller than the spacing between the gas planets.
For example, the spacing between Mercury and Venus is 0.7 AU - 0.4 AU = 0.3 AU while that between Earth and Venus is 1.0 AU - 0.7 AU = 0.3 AU.
Also, the spacing between Earth and Mars is 1.5 AU - 1.0 AU = 0.5 AU.
Also too, the spacing between the gas planets is shown below the spacing between Jupiter and Saturn is 9.6 AU - 5.2 AU = 4.4 AU while that between Uranus and Saturn is 19.6 AU - 9.6 AU = 10.0 AU.
Also, the spacing between Neptune and Uranus is 30 AU - 19.6 AU = 10.4 AU.
Thus, we can see that the spacing between the terrestrial planets is less than that between the gas planets.
Note that AU means astronomical unit and 1 AU is the distance between the Earth and the Sun. 1 AU = 1.50 × 10⁸ km
Chloe’s teacher gives her and her lab partner soil samples from different parts of the city: the park, the area next to a pond, the school, and a neighborhood. Chloe’s teacher also gives her a soil tester kit, which determines the pH of the soil. Chloe and her lab partner need to determine the pH of each soil sample and then compare them.
Fill in the blank with the word that best completes the statement.
This investigation is a(an)______investigation.
Answer:
an
Explanation:
It is AN because investigation starts with I ( i is a vowel). When there are vowels we use An.
Pls mark me brainliest!
Which of the following pairs of elements is most likely to form an ionic compound?
• magnesium and sodium
• nitrogen and sulfur
• oxygen and chlorine
• magnesium and chlorine
• carbon and fluorine
Explanation:
magnesium and sodium because they are minerals and part of iron
Which of the following statements regarding carbon is false? Group of answer choices Carbon has the capacity to form single and double bonds. Carbon has the ability to bond with up to six other atoms. Carbon has a tendency to form covalent bonds. Carbon has the ability to bond together to form extensive branched or unbranched "carbon skeletons."
Answer: The statement, carbon has the ability to bond with up to six other atoms is false.
Explanation:
Carbon is a group 14 element and it is a non-metal. The atomic number of carbon is 6 and its electronic distribution is 2, 4.
This means that there are 4 valence electrons present in it. Also, in order to attain stability a carbon atom forms only covalent bonds, that is, it shares its valence electrons with its own atoms or atoms of other elements.
Carbon has the capacity to form single and double bonds.
As valency of carbon is four so it can only combine to 4 other atoms vis single bond and it cannot bond with up to six other atoms.
Carbon shows the property of catenation, that is, it forms covalent bonds with its own atoms in a large number. So, carbon has the ability to bond together to form extensive branched or unbranched "carbon skeletons".
Thus, we can conclude that the statement, carbon has the ability to bond with up to six other atoms is false.
Which statement about the mass of an electron is correct? A The mass of an electron is equal to the mass of the proton. B The mass of an electron is less than the mass of the proton. с The mass of an electron is equal to the mass of a neutron. D The mass of an electron is greater than the mass of a neutron.
Answer:
B
Explanation:
because mass of an electron is 1/2000.
The statement about the mass of an electron which is correct is: B. The mass of an electron is less than the mass of the proton.
An atom refers to a smallest, indivisible unit that comprises the matter that forms all chemical elements. Therefore, atoms are typically considered as the fundamental building blocks of matter which determines the structure of a chemical element.
Basically, an atom consists of three (3) distinct particles and these include;
Protons. Neutrons. Electrons.
Electrons are the subatomic particles of a chemical element that are negatively charged with a magnitude of -1.
On the other hand, protons can be defined as the subatomic particles of a chemical element that are positively charged.
All of these subatomic particles of a chemical element has a mass. However, the mass of an electron is significantly less than the mass of proton, as a result of its extremely small size.
In conclusion, the mass of an electron is approximately 2000 times smaller than that of a proton and as such contributes almost nothing to the total mass of an atom.
Find more information: https://brainly.com/question/18214726
why do objects cool down
Answer:
wla dyan ang sagut ehh baka mali yan
Help!! Please explain how you get the answer
Answer:
5 moles
Explanation:
First, write out the balanced equation:
2Al + Fe₂O₃ → Al₂O₃ + 2Fe
Reaction ratio of Al to Fe₂O₃ is:
2 : 1
This means 2 moles of Al will react with 1 mole of Fe₂O₃
Al: 5 mol
Fe₂O₃: 3 mol
Multiply the reaction to get moles of both reactants you have:
2 : 1 (×⁵/₂) = 5 : ⁵/₂
2 : 1 (×3) = 6 : 3
In other words, 5 moles of Al will react with ⁵/₂ moles of Fe₂O₃;
And 3 moles of Fe₂O₃ will react with 6 moles of Al;
But, we do not have 6 moles of Al, therefore only the 5 moles of Al available will react;
5 moles of Al reacts with ⁵/₂ moles of Fe₂O₃, as we can see from the ratios we calculated above, the remaining ¹/₂ mole of Fe₂O₃ will not react;
We say that Al is the limiting reactant because all the Al will react but all the Fe₂O₃ does not (i.e. it is in excess);
Next and last, the reaction ratio of Al to Fe is:
2 : 2 or, more simply 1 : 1
This means the moles of Al that reacts is the equal to the moles of Fe produced from the reaction;
We've established that 5 moles of Al will react with ⁵/₂ moles of Fe₂O₃, so 5 moles of Fe will also be produced (since the ratio is 1 : 1);
You could also work this out using the moles of Fe₂O₃ that react;
The reaction ratio of Fe₂O₃ to Fe:
1 : 2
So the moles of Fe produced is 2× the moles of Fe₂O₃;
If ⁵/₂ moles of Fe₂O₃ reacts, then simply multiply this by 2 which is 5 moles
WHAT IS THE STOCK NAME FOR FeSO^3
Which substance is an electrolyte?
A)
C2H5OH(C)
B)
NaOH(s)
C)
H2(g)
D)
C6H1206 (s)
Answer:
B)NaOH(s)
Explanation:
what are the characteristics or properties that you can use to classify elements
Answer:
The number of outermost energy level electrons ( valency electrons )
The atomic number
explain how ships made of steel float on water
Answer:
The air that is inside a ship is much less dense than water. That's what keeps it floating
Question 14 of 30
Which of the following elements has 1 valence electron?
The Periodic Table
A. Sodium (Na)
B. Chlorine (CI)
C. Calcium (Ca)
D. Helium (He)
SUBMIT
Answer:
A. Sodium (Na)
Explanation:
The total number of electrons in the outermost principal energy level of an element is called the valence electrons of that element.
Na (11)---→1s2 2s2 2p6 3s1
There 1 electron in the outermost principal energy level of Sodium. So, the number of valence electron of Sodium is 11.
Answer:
Na
Explanation:
I was learning about it recently, that dude's right, it's Sodium
A magnesium ion, Mg2+, is formed from a magnesium atom, Mg.
Which row about the numbers of protons and neutrons in the magnesium ion and in the magnesium atom is correct?
Why the answer for this question is B.
Pls help to explain it. Thank you.
Answer:
The correct row is B.
Explanation:
The formation of the magnesium ion, Mg²⁺, comes from the removal of 2 electrons from the valence shell of the magnesium atom. Since the remotion is of electrons, the nucleus of the atom remains the same, so the number of protons and the number of neutrons does not change.
If the number of proton change, then the atom also change, since the identity of an atom is related to the atomic number which is the same to the proton number.
Now, if the number of neutrons changes, then we would be in the presence of an isotope of the magnesium atom.
Therefore, the correct row is B.
I hope it helps you!
What happens to the freezing point of a solution when more solute is added?
Hydrogen and nitrogen react to form ammonia. The chemical equation for this reaction is shown here. 3 H2(g) + N2(g) 2 NH3(g). What amount of hydrogen will produce 44.0 mol of ammonia?
66.0 mol
88.0 mol
132.0 mol
29.3 mol
Answer:
someone already answered but i think it's 132.0 mol too
What is the empirical formula of a compound containing 5.03 g carbon, 0.42 g hydrogen, and 44.5 g of chlorine
Answer:
CHCl₃
Explanation:
We have the following data:
C = 5.03 g
H = 0.42 g
Cl= 44.5 g
First, we divide each mass by the molar mass (MM) of the chemical element to calculate the moles:
MM(C) = 12 g/mol
moles of C = mass/MM(C) = 5.03 g/(12 g/mol) = 0.42 mol C
MM(H) = 1 g/mol
moles of H = mass/MM(H) = 0.42 g/(1 g/mol) = 0.42 mol H
MM(Cl) = 35.4 g/mol
moles of Cl = mass/MM(Cl) = 44.5 g/(35.4 g/mol) = 1.26 mol Cl
Now, we divide the moles by the smallest number of moles (0.42):
0.42 mol C/0.42 = 1 C
0.42 mol H/0.42 = 1 H
1.26 mol Cl/0.42 = 3 Cl
Thus, the C:H:Cl ratio is 1:1:3.
Therefore, the empirical formula is CHCl₃
Answer:
CHCl₃
Explanation:
A doctor is testing a new medication and he doesn’t tell the people in the study about the possible side effects of the medicine. He is _____.
An apple has been left out, and it is starting to rot. Which of the following is the best method to slow down the chemical changes that are occurring?
The best method is to keep rinsing the apple with water every hour.
The best method is to keep the apple in a cooler place.
The best method is to put the apple in the sun to warm it up.
The best method is to wrap the apple in plastic.
How do countries with different currencies trade goods with each other?
A.
They trade actual physical products to avoid confusion over currency differences.
B.
They negotiate to determine which country's currency will be used for the whole exchange.
C.
They create a new shared currency, such as the European Union countries' euro.
D.
They use the exchange rate to convert one country's currency to another's.
Answer:
D- They use the exchange rate to convert one's Country's currency to another's
Explanation:
what is an earthquake's epicenter found
Answer:
an epicenter is where an earthquake first hit
Answer:
The epicenter
Explanation:
The location below the earth's surface where the earthquake starts is called the hypocenter, and the location directly above it on the surface of the earth is called the epicenter. ... These are smaller earthquakes that occur afterwards in the same place as the mainshock.
Calculate the standard enthalpy change for the reaction 2A+B⇌2C+2D Use the following data: Substance ΔH∘f (kJ/mol) A -235 B -413 C 193 D -493
Answer:
ΔH = 283kJ/mol
Explanation:
Using Hess's law, the ΔH of a reaction is equal to the sum of ΔH° of products times its coefficient subtracting the sum of ΔH° of reactants times its coefficient. Replacing, for the reaction:
ΔH = 2ΔH°C + 2ΔH°D - (2ΔH°A+ΔH°B)
ΔH = 2*193kJ/mol + 2*-493kJ/mol - (2*-235kJ/mol+ (-413kJ/mol)
ΔH = 283kJ/molThe electronegativities of carbon and sulfur are almost the same. Both elements form covalently bonded compounds with hydrogen. Why is hydrogen sulfide a polar compound while methane is a nonpolar compound?
a.Sulfur has a stronger attraction for electrons than does carbon
b.A hydrogen sulfide molecule has lone pairs of electrons
c.Sulfur forms ionic bonds with hydrogen while carbon forms covalent bonds
d.Sulfur ions are larger than carbon ions
Answer:
b. A hydrogen sulfide molecule has lone pairs of electrons
Explanation:
The presence of lone pairs indictates that the molecule will be polar unless its molecular geometry is linear or square planar. In the case of H2S, its shape is bent due to the lone pair and it is a slightly polar molecule.
How many centimeters are in 5 miles? Hint: 1 miles = 5280 feet
Which kind of energy is stored in the chemical bonds of molecules found in
wood?
A. Mechanical energy
B. Potential energy
C. Gravitational energy
D. Kinetic energy
Answer:
B. Potential energy
Explanation:
It's not mechanical energy, because it is not doing work
It's not kinetic energy because it;s not moving
It's not gravitational energy because it is not above the ground
It is potential energy because it is stored energy