Answer:
C.
Explanation:
Luster
True or false? To prepare 20.0 mL of 2.00 M solution of hydrochloric acid from a 10.0 M stock solution, you should take 4.00 mL of the stock solution and add 20.0 mL of water.
False. To prepare 20.0 mL of 2.00 M solution of hydrochloric acid from 10.0 M stock solution, 4.0 mL of the stock solution and 16.0 mL of water would be needed.
Recall the law of diffusion that:
C1V1 = C2V2, where C1 = initial concentration, V1 = initial volume, C2 = final concentration, and V2 = final volume.
In this case, if C1 =10.0 M, V1 = ?, C2 = 2.00 M and V2 = 20.0 mL
V1 = 2 x 20/10
= 4.0 mL
Hence, 4.0 mL of the stock solution would be taken. Since the final volume is 20.0 mL, only 16.0 mL of water would need to be added and not 20.0 mL.
More on dilution can be found here: https://brainly.com/question/13844449
Ohio Achievement Test Coach Science, Grade 5
10. Bob first blows whistle hard. Then he blows the same whistle gently. What
changed when Bob blew the whistle the second time?
POSTTEST
A pitch
B. volume
C. pitch and volume
D. frequency
This is agree or disagree I need help ASAP!!
Answer:
disagree
sometimes they attract
Explanation:
Answer:
Explanation:
2. Agree
3. Agree
4. Agree
5. agree
6. disagree
If im wrong its because im tired lol
The nucleus of an atom is ______ charged
Answer:
The nucleus of an atom is positively charged.
Explanation:
The nucleus of an atom is positively charged because :
The nucleus is a small dense region at the center of the atom. It consists of a positive protons and neutral neutrons. so, It has an overall positive charged.
Different substances have....
A.the same properties
B. different properties
C.similar properties
D.all properties
Answer:
Different properties
Explanation:
They are different.
What is the percent composition (by mass) of MgBr2?
Answer:
13.2% Mg, 86.8% Br
Explanation:
Mg has a molar mass of 24.31g/mol.
Bromine has a molar mass of 79.90 g/mol.
There is one mole of Mg and two moles of Br in the compound:
79.90x2 + 24.31 = 184.11
So the total molar mass of MgBr2 is 184.11.
A percent tells us a part of a whole, so we will divide each part of the mass into the whole mass.
24.31g Mg / 184.11g MgBr2 = .132
159.8g Br / 184.11g MgBr2 = .868
Multiply these decimals by 100 to make them into a percent.
.132 x 100 = 13.2% Mg
.868 x 100 = 86.8% Br
how many periods are there in the modern periodic table of elements?
Answer:
There are seven periods in the modern periodic table.
Answer:
Seven periods
Explanation:
There are seven periods in the periodic table, with each one beginning at the far left. A new period begins when a new principal energy level begins filling with electrons. Period 1 has only two elements (hydrogen and helium), while periods 2 and 3 have 8 elements.
i have a quiz yall help
How many moles are in a 18 L tank of nitrogen gas at STP?
Answer:
12
Explanation:
i feel like its 12 because moles are medium sized but are they adult moles or baby moles or growing moles
Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore, 0.803moles of nitrogen gas are there in a 18 L tank of nitrogen gas at STP.
What is mole?The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity or amount of substance. We know one mole of any element contains 6.022×10²³ atoms which is also called Avogadro number.
Mathematically,
number of moles of any ideal gas =given volume ÷Volume occupied by one mole of a ideal gas at STP
Volume occupied by one mole of a ideal gas at STP=22.4L
given volume of nitrogen gas= 18 L
substituting all the given values in the above equation we get,
number of moles of nitrogen gas =18 L ÷22.4L
number of moles of nitrogen gas =0.803moles
Therefore, 0.803moles of nitrogen gas are there in a 18 L tank of nitrogen gas at STP.
To know more about mole, here:
https://brainly.com/question/15209553
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if life had existed during thie won the fossils probably would not have survived because
Answer:
because life would have use fossil for their benefits.
transmutation occurs during which type of radioactive decay
Explanation:
Transmutation, conversion of one chemical element into another. A transmutation entails a change in the structure of atomic nuclei and hence may be induced by a nuclear reaction (q.v.), such as neutron capture, or occur spontaneously by radioactive decay, such as alpha decay and beta decay (qq. v.).
Because the triple beam balance is zeroed before it is put into use, it measures
A.
volume
B.
weight
C.
the effects of gravity
D.
mass
Which statement is correct?
A. Physical changes produce new substances; chemical changes do not.
B. Chemical changes produce new substances; physical changes do not.
C. Both physical changes and chemical changes produce new substances.
D. Neither physical changes nor chemical changes produce new substances.
Answer:
B. Chemical changes produce new substances; physical changes do not.
Explanation:
Physical changes only alter appearances, while chemical changes are interactions that create new chemical formulas.
Determine the representative particles of
0.075 mol Ti
2.10 mol CO2
Answer:
0.o75 mol Ti = 4.5x10∧22
2.10 mol CO2 = 1.26x10∧24 molecules
hope this helped
A student asks why the ashes from a fire have much lower mass than the wood that was burned. Which of the following is the correct answer to the student's question?
Answer:
It have lower mass because much of the ashes came from the burned wood. (ashes were like little parts of the wood). plus most of the fuel was turned in to fire (light and heat energy) so yeah ash is just the left over.
Explanation:
Ammonia (NH3) dissolved in water is heated in a beaker. If initially there had been 60 grams dissolved in 100 grams of water, what would happen if the temperature reached 90℃ and why? A. The solution would become supersaturated and the ammonia would all remain dissolved . B. The solution would become saturated but the amount of ammonia dissolved would remain the same . C. about 50 more grams of ammonia would be able to dissolve as the solution has become unsaturated . D. about 50 grams of ammonia would come out of solution as the temperature caused the solubility to decrease .
Answer:
C. About 50 more grams ammonia would be able to dissolve as the solution has become unsaturated
Explanation:
From the question, we have;
The mass of ammonia dissolved in water = 60 grams
The mass of the water solvent which dissolves the ammonia = 100 g
The temperature to which the ammonia water solution is raised = 90°C
Therefore, given that the solubility of a solute in a solvent increases with temperature, when the temperature is raised, we have, that the solution will more unsaturated and will be able to dissolve more ammonia, therefore, option 'C' is the most correct option that corresponds with the relationship of temperature and solubility
You are melting a chocolate and accidentally have the stove up to high. the chocolate starts to burn on the bottom of your pot. Physical or Chemical Change?
Answer:
it is a chemical change because it can't be change back to it normal position when it gets burnt
Plants and animals need to protect themselves to survive. Select the statement that best describes the adaptions of animals and plants.
What is the mass in grams of 4.8 moles of Calcium Hydroxide?
Answer:
355.2 grams
Explanation:
m = M×n= (40 + 2(16+1))×4.8= 355.2 (g)
How is a calorimeter used in this experiment different from the ones used to find the energy content of a snack
Answer:
Kindly check the explanation section.
Explanation:
PS: Note that enough information are not being provided and we do not know the experiment this question is all about. However, some information are provided below which is going to aid in solving when you get access to the main question.
The determination of the heat transferred from one substance to another is one of the important aspect in science. The method in which this heat is being measured is known as calorimetry and the instrument used in this technique is known as the calorimeter.
When the energy content of a snack is needed to be calculated, there is the need use a type of instrument known as bomb calorimeter.
Most of the calorimeters used by students are not so expensive like the used in the industries. Most of these calorimeters operates at a constant pressure while the Bomb Calorimeter operates at constant volume.
What happens during high tide?
a.The tidal range is at its minimum in a location.
b.The tidal range is at its maximum in a location.
c.The water level in the ocean rises to above average water level.
D.The water level in the ocean drops to below average water level.
Answer: c
Explanation:
help please see attached file
Answer:
balanced equation of glucose
6CO2 + 6H2O----------C6H12O6 + 6O2
in the presence of sun light.
The large number before a molecule in a chemical formula is called a _______________.
O subscript
O coefficient
O equation
Answer:
Subscript
Explanation:
The little number you see to the right of the symbol for an element is called a subscript. That number indicates the number of atoms of that element present in the compound. When balancing an equation, you can change the coefficients but not the subscripts.
hope this helps! if not, it's got to be coefficient or equation
If 3.91 moles of H2 were used, how many moles of NH3 would be made?
HELP PLEASE ASAP
N + H2 → NH3
balance the equation
2N + 3H2 → 2NH3
3H2 → 2NH3
3 : 2
3.91 ÷ 3 = 1.303 mol
1.3 × 2 = 2.606 mol
As the randomness of a system increases, the entropy of the system:
A) decreases
B) increases
C) remains the same
Answer:
it most likely increases
Will award brainliest! Between which two ionization energies would you expect to see the biggest jump for calcium? A. 11-12
B. 12-13
C. 13-14
D. 14-15
answer:lettter B that is answer
When one element replaces another element the reaction is known as a _ replacement reaction
Answer:
Single replacement reaction
Explanation:
A single replacement reaction, sometimes called a single displacement reaction, is a reaction in which one element is substituted for another element in a compound.
Can you build a fire on the moon? Why or why not?
Answer:
No.
Explanation:
We can't build a fire on the moon, because moon's atmosphere lacks oxygen.
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No lightning of a fire on the surface of the moon is impossible..
[tex] \huge \green {reasons - }[/tex]
surface of the moon lacks oxygen which is important for the formation of fire.Surface of the moon doesn't have wind which disables the fire to burn rapidly.Which of these do NOT show malleability a) Iron
b) Sulfur
c) Copper
d) Aluminum
Answer:Sulfur
Hope this helps!
Explanation:
The greater the difference in EN (electronegativity) between the intramolecular bonding of two atoms, the bond will experience more ionic behavior. A. True b. False
A sample of gas has a volume of 12.0 L and a pressure of 2.00 ATM. If the pressure of gas is increased to6.00 ATM, what is the new volume of the gas
Answer:
4L
Explanation: