Explanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\[/tex]
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
We have
[tex]n = \frac{8.3 \times {10}^{12} }{6.02 \times {10}^{23} } \\ \\ \\ \\ \: \: \: \: \: \: \: = 1.379 \times {10}^{ - 11} \: \: \: \: moles[/tex]
Hope this helps you
An atom of element X has an atomic number of 11 and a mass number of 23. .
a) What is the definition of atomic number?
b) How many protons, electrons and neutrons are in this atom?
c) A different atom of X has an atomic number of 11, but a mass number of 24. Give a
name for these two forms of X.
d) Would these two atoms have similar chemical properties? Give a reason for your
answer.
Answer:
ssaasasasassdsdsdafdftrga*b*y/a la 3
Explanation:
Answer:
a) the number of protons in an atom
b) 11 protons, 11 electrons and 12 neutrons.
c) Isotope
d) yes, they still have the same number of protons and electrons.
Explanation:
b) Number of neutrons = mass number - atomic number
Atoms have the same number of electrons and protons
c) isotopes are atoms with the same number of protons but a different number of neutrons.
Hope this helped !
What is the pH of the solution if the [H3O+] concentration is 2.5 X 10-4 M?
HELP I'M DESPERATE! NO LINK!
Answer:
3.60
Explanation:
To calculate the pH of any solution, use the formula;
pH= -log[ concentration ] and for this case take pH= -log[H3O+]
= -log[2.5x10^-4]
therefore pH= 3.60
The idea of pH mainly applies in the determination of the nature of various solutions to the used in the chemical analysis. The correct pH must be determined in order to get accurate results. Ionic equillibria mostly involves the calculations involving pH which is normally obtained after determination of equilibrium concentrations.
A 3.0 g sample of a gas occupies a volume of 1.00L at 100C and 740 torr pressure. The molecular weight of the
(Give the same ANSWER for the next TWO problems)
gas is
Answer:
94.2 g/mol
Explanation:
Ideal Gases Law can useful to solve this
P . V = n . R . T
We need to make some conversions
740 Torr . 1 atm/ 760 Torr = 0.974 atm
100°C + 273 = 373K
Let's replace the values
0.974 atm . 1 L = n . 0.082 L.atm/ mol.K . 373K
n will determine the number of moles
(0.974 atm . 1 L) / (0.082 L.atm/ mol.K . 373K)
n = 0.032 moles
This amount is the weigh for 3 g of gas. How many grams does 1 mol weighs?
Molecular weight → g/mol → 3 g/0.032 moles = 94.2 g/mol
Which is a definite sign of a chemical reaction?
Chemical properties change.
Physical properties change.
A gas forms.
A solid forms
Answer: here i am choosing two answer because i am not sure . a gas forms and a solid forms
Explanation: a solid forms thus is to say a precipitate is formed
a gas forms thus to say effervescence , fizzing and bubbling whiles a gas is being produced.
What is the molarity of a Ba(OH)2 solution if 93.9 mL is completely titrated by 15.3 mL of 0.247 M H2SO4?
show work please!! i am not 100 percent sure how to do this so i would like to see steps if possible
Answer:
0.04 M.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
Ba(OH)₂ + H₂SO₄ —> BaSO₄ + 2H₂O
From the balanced equation above,
The mole ratio of acid, H₂SO₄ (nₐ) = 1
The mole ratio of base, Ba(OH)₂ (n₆) = 1
Finally, we shall determine the molarity of Ba(OH)₂ solution. This can be obtained as follow:
Volume of base, Ba(OH)₂ (V₆) = 93.9 mL
Volume of acid, H₂SO₄ (Vₐ) = 15.3 mL
Molarity of acid, H₂SO₄ (Mₐ) = 0.247 M
Molarity of base, Ba(OH)₂ (M₆) =?
MₐVₐ / M₆V₆ = nₐ / n₆
0.247 × 15.3 / M₆ × 93.9 = 1/1
3.7791 / M₆ × 93.9 = 1
Cross multiply
M₆ × 93.9 = 3.7791
Divide both side by 93.9
M₆ = 3.7791 / 93.9
M₆ = 0.04 M
Therefore, the molarity of the Ba(OH)₂ solution is 0.04 M
What is the name of this hydrocarbon?
Answer:
2,3-dimetylpentane
Explanation:
.....................
True or False?
A day is about 12 hours long
Answer:
false it's 24 hours long.
.
What primarily causes the spread of acid rain?
through groundwater and aquifers
through streams and rivers
through the atmosphere
through ocean currents
Answer:
(C) through the atmosphere
Explanation:
How would the number of atoms in a 2.02g sample of hydrogen compare to the number of atoms in a 32.00g sample of oxygen
Answer:
Number of atoms is equal.
Explanation:
1 mol of anything contains NA particles.
NA is known as Avogadro's number, 6.02×10²³
We determined the moles of each compound. Both molecules are dyatomic,
H₂ → 2.02 g . 1mol / 2.016 g = 1 mol
O₂ → 32 g . 1mol / 32g = 1 mol
Both have the same amount of moles.
In conclussion, the number of atoms is the same in both samples.
Scientists, emergency personnel, and the weather service keep a close eye on this potential natural disaster that impacts Florida several times each year. What is this disaster being tracked here?
Answer:
hurricane
Explanation:
help plz Question 8(Multiple Choice Worth 2 points)
(01.05 LC)
Which states of matter have the same volume when moved?
Gases and liquids
Gases and solids
Liquids and solids
Solids, liquids, and gases
Explanation:
(Gases and liquids )
is the answer
Gases and liquids are the states of matter that have the same volume when moved.
Hope it helps you
positivities and negativity of computer creativity
answerrr BRAINLIEST PLS FAST
Explanation:
Some of the positive effects are faster communication, an organization of data and information, computerization of tasks, and easier access to the information. Some of the negative effects of computers are human's break their social interact with friends and families, cause back problem, depression, and poor health.Answer:
Creativity is a phenomenon whereby something somehow new and somehow valuable is formed. The created item may be intangible (such as an idea, a scientific theory, a musical composition, or a joke) or a physical object (such as an invention, a printed literary work, or a painting).
Scholarly interest in creativity is found in a number of disciplines, primarily psychology, business studies, and cognitive science, but also education, the humanities, technology, engineering, philosophy (particularly philosophy of science), theology, sociology, linguistics, the arts, economics, and mathematics, covering the relations between creativity and general intelligence, personality type, mental and neural processes, mental health, or artificial intelligence; the potential for fostering creativity through education and training; the fostering of creativity for national economic benefit, and the application of creative resources to improve the effectiveness of teaching and learning.

A picture of a lightbulb is associated with someone having an idea, an example of creativity.
What is natural gas and how does it work
Answer:
Natural Gas is a fossil energy source that formed deep beneath the Earth's surface. It is used in power plants to generate electricity by burning natural gas as their fuel.
Explanation: I hope this helped :)
Answer:
A molecule of natural gas is made up of carbon and hydrogen. When the hydrogen is segregated from the carbon and filled into a fuel cell, it fuses with oxygen to produce water, electricity, and heat. The carbon is released as carbon dioxide in smaller quantities than from gas turbines.
Explanation:
This is the site I got the info from :
How Natural Gas Works | Peak Oilhttps://www.peakoil.net › non-renewable › how-natural-g
15.True or False:
The concentration of a solution can be increased indefinitely by
adding solute
which of the following best describes the use of a non renewable resource?
Answer:
Non-renewable resources, such as coal and oil, are the primary source of power in the world, and they are used to power vehicles, factories, and homes. Although affordable, they can be harmful to the environment and are one of the notable contributors to global warming.
Explanation:
source:cfi
Two firefighters are trying to break through a door. One firefighter is heavy, and the other is light. If they run at the same speed, which one is more likely to break through?
Answer:
the heavy one
Explanation:
the heavy one because heavy things and break things and the light one can't
Which is the correct Lewis dot structure of NH2?
H-N-H
H-N-H
A.
B.
N-H-H
H-N-H
C.
D.
-H-N-H
E.
ОА А
ов. В
C C
OD D
ОЕ Е
Answer:
D
Explanation:
100 POINTS!!! AND BRAINLIEST!!!
This tree species was preserved as a fossil in the Arizona desert. The species is now extinct. Describe what the environment was like when the tree lived and how it is different now. Then, infer why this type of tree and other living things that lived with it are extinct.
Under Adolf Hitler, Germany violated the Treaty of Versailles by expanding its
military and occupying the Rhineland. How did the League of Nations respond to
these violations?
The League of Nations issued a declaration of war on Germany.
O The League of Nations condemned the violations but took no other action.
O The League of Nations imposed harsh sanctions on Germany.
The League of Nations sent a multinational peacekeeping force to the region.
Answer:
B. The League of Nations condemned the violations but took no other action.
Explanation:
Nazi leader, Adolf Hitler violated the Treaty of Versailles by sending German military forces in Rhineland. He not only violated the Treaty of Versailles but the Locarno Pact also.
The treaty was signed in 1919 to end the war between Germany and the Allied Powers.
Even after Adolf Hitler violated the treaty, the League Nations did not take any actions.
Therefore, option B is correct.
TVINN
Assertion: Naphthalene,
camphor, iodine, ammonium
chloride are some common
examples of the substances
which undergo sublimation.
Reason: All solids are first
converted to liquids and then
gases on heating.
Both assertion (A) and
Reason (R) are true
and Reason (R) is the
correct explanation of
assertion (A)
Both assertion (A) and
reason (R) are true but
reason (R) is not the
correct explanation of
assertion (A)
w
Assertion (A) is true
but reason (R) is false.
Assertion (A) is false but reason (R)is true.
Answer:
Assertion (A) is true
but reason (R) is false.
Explanation:
If we look at the assertion closely, it is true that a sublime substance changes from solid to gas without passing through a liquid state. Naphthalene, camphor, iodine and ammonium chloride are some common examples of the substances which undergo sublimation.
However, not all solids first pass through a liquid state before converting to gas. Sublime solids such as those listed above passes directly from solid to gas without passing through a liquid state.
Hence the assertion is true but reason is false.
A solution has pH of 9 what is it?
When 250 ml of water is added to 35 ml of 0.2 M HCl
Cu1+ and O2- what is the formula and what is the name of it
Answer:
copper I oxide
Explanation:
Copper is known to form two oxides; copper I oxide and copper II oxide.
In the question we have the ions; Cu1+ and O2-. Ionic compounds are formed by a combination of ions as typified below;
Cu^+ + O^2- -------> Cu2O
This compound is copper I oxide
CuSO4 + 2NaBr --> CuBr2 + Na2SO4 ? How many grams of CuSO4 are needed to react with 1.80 x 1024 molecules of NaBr?
Answer:
[tex]238.5gCuSO_4[/tex]
Explanation:
Hello there!
In this case, by considering the given chemical reaction, it is possible for us to calculate the required grams of CuSO4 by considering its molar mass of 159.6 g/mol, the given molecules of NaBr, the Avogadro's number and the 1:2 mole ratio between these two in order to set up the following stoichiometric set up:
[tex]1.80x10^{24}moleculesNaBr*\frac{1molNaBr}{6.022x10^{23}molecules NaBr}*\frac{1molCuSO_4}{2molNaBr} *\frac{159.6gCuSO_4}{1molCuSO_4}\\\\=238.5gCuSO_4[/tex]
Best regards!
For H 3 PO 4 and H 3 BO 3 , does the subscript " of hydrogen in these two formulas seem to result in additional ions in solution as it did in Group A? Explain .
Answer:
See Explanation
Explanation:
Let us consider the ionization of these compounds;
H3PO4 ⇔3H^+ + PO4^3-
H3BO3 ⇔3H^+ + BO3^3-
The next to consider is the type of electrolyte the both solution are; the both solutions are weak electrolytes and weak electrolytes do not ionize to a large extent.
The implication of this is that, not so much number of ions is added to the solution due to the poor ionization of these weak electrolytes. Hence, in spite of the subscript of 3, the conductivity of the solution does not significantly improve for the reason stated here quite unlike when strong electrolytes are used.
You are performing a titration with 0.80 M sodium hydroxide as a standard. Estimate how much would be needed to change 125 mL of a 2.0 M solution of nitric acid to a faint pink endpoint.
Answer:
312.5 mL
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
HNO₃ + NaOH —> NaNO₃ + H₂O
From the balanced equation above,
The mole ratio of acid, HNO₃ (nₐ) = 1
The mole ratio of base, NaOH (n₆) = 1
Finally, we shall determine the volume of the base, NaOH needed for the reaction. This can be obtained as follow:
Molarity of base, NaOH (M₆) = 0.08 M
Volume of acid, HNO₃ (Vₐ) = 125 mL
Molarity of acid, HNO₃ (Mₐ) = 2 M
Volume of base, NaOH (V₆) =?
MₐVₐ / M₆V₆ = nₐ/n₆
2 × 125 / 0.80 × V₆ = 1/1
250 / 0.80 × V₆ = 1
Cross multiply
0.80 × V₆ = 250
Divide both side by 0.8
V₆ = 250 / 0.8
V₆ = 312.5 mL
Thus, the volume of the base, NaOH needed for the reaction is 312.5 mL
2C2H6 + 7O2 → __CO2 + 6H2O
What coefficient will need to be placed in the blank in order for the following equation to be correctly balanced?
A.
1
B.
3
C.
4
D.
7
Answer:
From the Combustion formula of Organic Compounds....
Exactly 4 Moles of CO2 would make the equation balanced
So
OPTION C
4MOLES
The transmission of thermal energy that is caused by the flow of a fluid’s particles. It can only occur with liquids and gases is...
HELP ASAP 10 POINTSSS
In this diagram, the medium on top is air and the medium on bottom is glass. Which vocab word best describes what is happening when the light wave passes from the air into the glass?
Question 2 options:
resolution
diffraction
refraction
reflection
Answer: refraction
Explanation: this is because during refraction light moves from one medium to another.
Please help me. I am doing a test and, I don’t know the answer.
Answer:
it's the third one ozone layer depletion