Answer:
No.4 is B No.5 is d
Explanation:
Answer:
Q 4: d
Explanation: this is all I can answer
How much NaOH (in grams) is needed to prepare 463 mL of solution with a pH of 10.020?
Answer: [tex]1.94\times 10^{-3}g[/tex] of NaOH
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution.
pH is calculated by taking negative logarithm of hydrogen ion concentration.
[tex]pH=-\log [H^+][/tex]
Putting in the values:
[tex]10.020=-\log[H^+][/tex]
[tex][H^+]=9.55\times 10^{-11}[/tex]
[tex][H^+][OH^-]=10^{-14}[/tex]
[tex][OH^-]=\frac{10^{-14}}{9.55\times 10^{-11}}=1.05\times 10^{-4}M[/tex]
[tex]NaOH\rightarrow Na^++OH^-[/tex]
[tex]Molarity=\frac{moles\times 1000}{\text {Volume in ml}}[/tex]
[tex]1.05\times 10^{-4}M=\frac{moles\times 1000}{463ml}[/tex]
moles = [tex]4.86\times 10^{-5}[/tex]
Mass of [tex]NaOH=moles\times {\text {Molar mass}}=4.86\times 10^{-5}\times 40=1.94\times 10^{-3}g[/tex]
Thus [tex]1.94\times 10^{-3}g[/tex] of NaOH is needed to prepare 463 mL of solution with a pH of 10.020
What is heat of vaporization?
ОА.
It is the heat required to change a substance's temperature by 1°C.
OB.
It is the heat required to change a gram of substance from a solid to a liquid.
Ос.
It is the heat required to change a substance from a solid directly to a gas.
OD.
It is the heat required to change a gram of substance from a liquid to a gas.
O E. It is the heat required to separate one substance into two substances.
Answer:
Your answer is D. It is the heat required to change a gram of substance from a liquid to a gas.
Which best describes heating by convection?
Air molecules touch the warm ground, heating it up.
Warm air rises and takes heat with it; eventually it cools and sinks.
Sunlight travels through empty space without the aid of fluids or solids.
modern vacuum techniques make it possible to reach a pressure of 1.00 * 10 ^ -10 mm Hg in a laboratory system. what volume in milliliters would 1.00 * 10 ^ 6 molecules of gas occupy at this pressure and standard temp?
Answer:
around 0.283
Explanation:
Balance the following equation by adding the correct mole numbers.
P⁴+Cl²->PCl³
Hey there!
P₄ + Cl₂ → PCl₃
First, let's balance Cl.
There are 2 on the left, and 3 on the right.
To balance this, let's put a coefficient of 3 in front of Cl₂ and a coefficient of 2 in front of PCl₃.
P₄ + 3Cl₂ → 2PCl₃
Now we have 6 on the left and 6 on the right.
Next, let's balance P.
There are 4 on the left and 2 on the right.
Let's change the coefficient in front of PCl₃ from 2 to 4.
P₄ + 3Cl₂ → 4PCl₃
There are now 4 P on each side.
However, now Cl is unbalanced, with 6 on the left and 12 on the right.
We can change the coefficient in front of Cl₂ from 3 to 6.
P₄ + 6Cl₂ → 4PCl₃
So now, we have 4 P on each side and 12 C on each side.
This is our final balanced equation.
Hope this helps!
Answer:
1:1
Explanation:
Took test
Create a Element #Brainliest Challenge
Rules- It must Have Atomic mass and Number and it's Fictional name you created
For Fun Add #GoGenius
Answer:
NeHe
Explanation:
Atomic Mass: 24.182302
Number: 18
I don't know, I just made it up.
What is the meaning of the red moon??
Answer:
the red moon occurs during lunar eclipse
Explanation:
The reddish coloration arises because sunlight reaching the Moon must pass through a long and dense layer of Earth's atmosphere, where it is scattered
Relate dark matter to the development of the universe after the Big Bang. In 3-5 sentences, speculate on how the development of the universe would have been different if there had been no dark matter. In your answer, use the term structures.
Please answer this and ill mark you as brainliest
Answer:
Dark matter also called baronic matter is the matter that makes up 27% of the universe.
In 1933 it was determined as that mass that cannot be seen, that is, the non-visible mass of outer space.
Dark matter also plays a central role in the formation of structures and the evolution of galaxies and has measurable effects on the anisotropy of cosmic microwave background radiation. The composition of this matter is unknown today.
The dark matter component has considerably more mass than the "visible" component of the Universe.
Explanation:
There are certain researchers who say that the appearance of dark matter was before the appearance of the big bang.
A relevant fact of this matter is that dark matter exerts gravity, and that gravity affects the movements of objects.
Despite the fact that nothing is known about its origin, astronomers have amply demonstrated that dark matter plays a determining role in the formation of galaxies and galactic clusters, which could not maintain their cohesion without its existence, but many doubt that it is the remainder / remnant or product of a big bang.
when the surface of a mirror curves inward, like the inside of a bowl, it is called a ____.
A) plane mirror
B) convex mirror
C) concave mirror
D) diffuse mirror
Answer:
C
Explanation:
The answer is always C
Answer:C. Concave mirror
Explanation:
When the surface of a mirror curves inward, like the inside of a bowl, it is called c. Concave mirror.
How is a lithium atom (Li) different from a lithium ion (Li+)?
Li has fewer electrons than Li+
Li has more electrons than Li+
Li has fewer protons than Li+
Li has more protons than Li+
Answer:
Li has fewer protons than Li+
The oxidation number of bromine in bromine gas is _____. A. 0 B. +1 C. –1 D. –2
Answer:
the answer is 0
The answer to the question is
A. 0
If 50.0 g of KCl reacts with 50.0 g of O2 to produce KClO3 according to the following equation, how many grams of KClO3 will be formed? Word and Formula equation.
Answer:
A. 82.2g of KClO3
B. Word equation:
50g of KCl react with 50g of O2 to produce 82.2g of KClO3
C. Formula equation:
2KCl + 3O2 —> 2KClO3
Explanation:
The balanced equation for the reaction. This is given below:
2KCl + 3O2 —> 2KClO3
Next, we shall determine the masses of KCl and O2 that reacted and the mass of KClO3 produced from the balanced equation. This is illustrated below:
Molar Mass of KCl = 39 + 35.5 = 74.5g/mol
Mass of KCl from the balanced equation = 2 x 74.5 = 149g
Molar Mass of O2 = 16x2 = 32g/mol
Mass of O2 from the balanced equation = 3 x 32 = 96g
Molar Mass of KClO3 = 39 + 35.5 + (16x3) = 122.5g/mol
Mass of KClO3 from the balanced equation = 2 x 122.5 = 245g
Summary:
From the balanced equation above:
149g of KCl reacted.
96g of O2 reacted.
245g of KCl were produced.
Next, we shall determine the limiting reactant. This is illustrated below:
From the balanced equation above,
149g of KCl reacted with 96g of O2.
Therefore, 50g of KCl will react with = (50 x 96)/149 = 32.21g of O2.
Since a lesser mass of O2 ( i.e 32.21g) than what was given (i.e 50g) is needed to react completely with 50g of KCl, therefore, KCl is the limiting reactant and O2 is the excess reactant.
A. Determination of the mass of KClO3 produced from the reaction.
In this case the limiting reactant will be used.
From the balanced equation above,
149g of KCl reacted To produce 245g of KClO3.
Therefore, 50g of KCl will react to produce = (50 x 245)/149 = 82.2g of KClO3.
Therefore, 82.2g of KClO3 is produced from the reaction.
B. Word equation:
50g of KCl react with 50g of O2 to produce 82.2g of KClO3.
C. Formula equation:
2KCl + 3O2 —> 2KClO3
The mass of [tex]\rm KClO_3[/tex] produced has been 82.1085 g.
The word equation for the reaction has been: 50 gram potassium chloride reacts with 50 g oxygen to give 82.1085 g potassium chlorate.
The formula equation has been, [tex]\rm 2\;KCl\;+\;3\;O_2\;\rightarrow\;2\;KClO_3[/tex].
The balanced chemical equation for the reaction has been given as:
[tex]\rm 2\;KCl\;+\;3\;O_2\;\rightarrow\;2\;KClO_3[/tex]
Computation for Mass of Potassium chlorate:From the balanced chemical equation, 2 moles of KCl reacts with 3 moles of oxygen to give 2 moles of [tex]\rm KClO_3[/tex].
The moles of reactants have been given as:
[tex]\rm Moles=\dfrac{mass}{molar\;mass}[/tex]
The moles of 50 g KCl has been given as:
[tex]\rm Moles\;KCl=\dfrac{50}{74.55} \\Moles\;KCl=0.67\;mol[/tex]
The moles of KCl available has been 0.67 mol.
The moles of 50 g [tex]\rm O_2[/tex] has been given as:
[tex]\rm Moles\;O_2=\dfrac{50}{32}\\Moles\;O_2=1.5625\;mol[/tex]
The moles of 50 g [tex]\rm O_2[/tex] has been 1.5625 mol.
From the balanced equation, for 2 moles KCl, 3 moles oxygen has been required. For 0.67 mol KCl, oxygen required has been:
[tex]\rm 2\;mole\;KCl=3\;moles\;O_2\\0.67\;mol\;KCl=\dfrac{3}{2}\;\times\;0.67\;mol\;O_2\\0.67\;mol\;KCl=1.005\;mol\;O_2[/tex]
The available moles of oxygen has been 1.5625 mol. Thus, oxygen has been excess reactant and KCl has been limiting reactant.
The moles of [tex]\rm KClO_3[/tex] produced has been given as:
[tex]\rm 2\;mol\;KCl=2\;mol\;KClO_3\\0.67\;mol\;KCl=\dfrac{2}{2}\;\times\;0.67\;mol\;KClO_3\\0.67\;mol\;KCl=0.67\;mol\;KClO_3[/tex]
The moles of [tex]\rm KClO_3[/tex] produced has been 0.67 mol.
The mass of [tex]\rm KClO_3[/tex] produced has been:
[tex]\rm Mass=Moles\;\times\;molar\;mass\\Mass\;KCl=0.67\;\times\;122.55\;\\Mass\;of\;KCl=82.1085\;g[/tex]
The mass of [tex]\rm KClO_3[/tex] produced has been 82.1085 g.
The word equation for the reaction has been:
50 gram potassium chloride reacts with 50 g oxygen to give 82.1085 g potassium chlorate.
The formula equation has been, [tex]\rm 2\;KCl\;+\;3\;O_2\;\rightarrow\;2\;KClO_3[/tex].
For more information about chemical equation, refer to the link:
https://brainly.com/question/13350862
Which of the following are characteristics of heterogeneous mixtures
A. distinguishable components
B. evenly distributed components
C. particles too small to be seen with a microscope
D. components in varying proportions
E. particles that may settle
Answer:
c
Explanation:
PLEASE HELP :"( DUE NOW!!
What is the equation for the equilibrium constant for this equation?
CO+3H2⇌CH4+H2O
[H2O][H2]/[CH4][CO]
[CO][H2]3/[CH4][H2O]
[CH4][H2O]/[CO][H2]3
[CH]4[H2O]/[H2]3
Answer:
The correct answer is
[CH4][H2O]/[CO][H2]3
Option 3 is correct
Explanation:
Step 1: Data given
For the equation aA + bB ⇆ cC + dD
The equilibrium constant is [C]^c * [D]^d / [A]^a*[B]^b
Step 2: Calculate the equilibrium constant Kc
CO+3H2⇌CH4+H2O
Kc = [H2O][CH4] / [CO][H2]³
The correct answer is
[CH4][H2O]/[CO][H2]3
Option 3 is correct
What is the answer ?
Answer:
b
Explanation:
Electromagnetic waves are waves that have no medium to travel whereas mechanical waves need a medium for its transmission.
please helpppppppppp
Select the TRUE statements about the carbon cycle
The carbon cycle is the process in which carbon travels from the atmosphere into organisms and the Earth and then back into the atmosphere.
Plants take carbon dioxide from the air and use it to make food.
Animals eat food and the carbon is stored in their bodies or released during cellular respiration.
Water (H2O) is cycled around the Earth
the carbon cycle is the process in which carbon travels from the atmosphere into organisms and the earth and then back into the atmosphere
The specific heat of iron is 0.107 cal/g x oC. How much heat is transferred when a 24.7 kg iron ingot is cooled from 880 oC to 13 oC?
Answer:
heat = 229139.43 cal
Explanation:
given data
specific heat of iron is 0.107 cal/g-°C C = 0.4494 J/g°C;
Mass of iron = 24.7 kg = 24700 g
temperature T1 = 880°C
temperature T2 = 13°C
solution
we know that Heat lost that is express as
heat loss = mcΔT .........................1
here m is the mass and c is specific heat capacity of iron and ΔT is the change in temperature
so here change in the temperature is = 880°C - 13°C
change in the temperature = 867°C
so put here value and we get
heat = 24700 × 0.107 cal/g-°C × 867°C
heat = 229139.43 cal
ASAP NEED HELP PLSSS
A gas occupying a volume of 3.75L at a pressure of 0.980 arm is allowed to expand at constant temperature until its pressure reaches 0.641 atm. What is the final volume of the sample?
Answer:
Volume = 5.73L
Explanation:
Data;
V1 = 3.75L
P1 = 0.980atm
P2 = 0.641atm
V2 = ?
This question involves the use of Boyle's law, which states that, the volume of a fixed mass of gas is inversely proportional to its pressure provided that temperature remains constant.
Mathematically,
V = kP, k = PV
P1V1 = P2V2 =P3V3=........=PnVn
P1V1 = P2V2
V2 = (P1 * V1) / P2
V2 = (0.980 × 3.75) / 0.641
V2 = 5.73L
The final volume of the gas is 5.73L
How many total atoms from Carbon are present on the reactant side?
20 points
2CH2+202
O2+HC4
5
2
1
3
Answer:
2 carbon atoms/molecules are present on the reactant side.
hope it helps!
________________ substances have an equal amount of H+ and OH- ions in solution.
Answer:
Water, and other neutral
Explanation:
That means those substances have pH = 7.
When the amount of H+ is more than the amount of OH- in solution, the substance is acidic ( eg.: Lemon juice ). pH < 7
When the amount of H+ is less than the amount of OH- in solution, the substance is basic ( eg.: Baking soda ). pH > 7
the combustion of 0.1240 kg of propane in the presence of excess oxygen produces 0.3110kg of carbon dioxide what is the limittinf reacrant?
Answer:
Propane
Explanation:
From the question given, we were told that 0.1240 kg of propane reacted with excess oxygen to produce 0.3110kg of carbon dioxide.
Since the reaction took place in the presence of excess oxygen, therefore, propane is the limiting reactant as all of it is used up in the presence of excess oxygen.
Answer:
The limiting reactant is propane, C₃H₈ and the percentage yield is 83.77%
Explanation:
Mass of propane = 0.1240 kg = 124 g
Mass of carbon dioxide = 0.3110 kg = 311 g
Molar mass of propane = 44.1 g/mol
Molar mass of carbon dioxide = 44.01 g/mol
Number of moles of propane = 124/44.1 = 2.812 moles
Number of moles of carbon dioxide = 311/44.01 = 7.067 moles
Equation for the reaction
C₃H₈ + 5O₂ → 3CO₂ + 4H₂O
Hence 1 mole of propane ideally yields 3 moles of CO₂
Hence, 2.812 moles of propane will yield 3×2.812 moles = 8.44 moles of CO₂
Since, oxygen is in excess, therefore, the limiting reactant = Propane, C₃H₈
The percentage yield = 7.067/8.44× 100 = 83.77%.
how does the sun light affect earths climate
Answer:
The Sun powers life on Earth; it helps keep the planet warm enough for us to survive. It also influences Earth’s climate: We know subtle changes in Earth’s orbit around the Sun are responsible for the comings and goings of the past ice ages. But the warming we’ve seen over the last few decades is too rapid to be linked to changes in Earth’s orbit, and too large to be caused by solar activity
Explanation:
Review the following chemical equation: Find the molar ratio between C6H6 to
carbon dioxide, CO2. 2C6H6 + 1502 YEILDS 6H20 - 12C02
Answer:
[tex]\frac{1}{6}[/tex]
Explanation:
Molar ratio is defined as the ratio of number of moles of reactants or products in a balanced chemical equation.
In this balanced equation, the number of C6H6 molecules react to form 12 CO2 molecules.
Thus, the molar ratio between C6H6 to carbon will be equal to 2 moles of C6H6 divided by 12 moles of CO2
[tex]\frac{2}{12}\\\frac{1}{6}[/tex]
What is the correct answer? Please
Answer:
c
Explanation:
A student wants to increase the magnetic force between two bar magnets. What should the student do?
A
Make the positive poles face each other.
B
Move the magnets farther apart.
C
Make the negative poles face each other.
D
Move the magnets closer together.
Answer:
Option "D" is the correct answer to the following question:
Explanation:
Magnets usually have their pulling properties, which we call magnetic power.
A major feature of magnetic power is that the closer the magnets are brought together, the higher the magnetic force increases.
On increasing distance, the magnetic force starts to decrease.
So, we can say that students should bring magnets closer to each other to increase the magnetic power.
the distance from the top of one sound wave to the top of the next sound wave is called a (n)
Answer:
The answer is wavelength
Explanation:
How many atoms are there in 2 moles of helium?
Answer:
1 mole Of Helium = Weight of Helium/4Weight of Helium = 1*4 = 4 grams 1 mole of Helium contains 6.023*10²³ ( Avogadro number) atoms. Number of moles of in 4 grams of Hydrogen 4 grams is = given weight / molecular weight of Hydrogen (H₂) = 4/2 =2 Number of atoms/molecules in 2 moles of Hydrogen is (2*6.023*10²³) atoms. = 12.046*10²³ atoms.
(Hope this helps)
The number of atoms in 2 moles of helium is 1.204×10²⁴ atoms
From Avogadro's hypothesis,
1 mole of any substance = 6.02×10²³ atoms
Thus,
1 mole of helium = 6.02×10²³ atoms
With the above information in mind, we can obtain the number of atoms in 2 moles of helium as follow:
1 mole of helium = 6.02×10²³ atoms
Therefore,
2 moles of helium = 2 × 6.02×10²³ atoms
2 moles of helium = 1.204×10²⁴ atoms
Thus, we can conclude that 2 moles of helium contains 1.204×10²⁴ atoms
Learn more: https://brainly.com/question/24848191
Which of the following is the energy of moving electrons?
a. kinetic energy
b. thermal energy
c. nuclear energy
d. electrical energy
Answer:
Electrical energy
Explanation:
Electrical energy is caused by the moving of electrons.
hope it helps!
balancing equations
Answer:
4. 1HCL + 1NAOH- I NACL+1H2O
Explanation:
there is 2 hydrogens on the left side of the equation, balancing out to the other side of the equation. everything else would be balanced out too
Which is usually associated with a slower reaction rate?
A. using a whole solid in the reactants
B. adding heat energy to the reactants
C. adding food coloring to the reactants
D. using a strong solution of the reactants