Answer:
All the body cells in a human have the same hereditary information, meaning they have the same DNA because they came from one source (both parents). However, they have differences in the way they function and this is as a result of each cell in the body have a pool of DNA and then they can select the genes they would like their features to be expressed depending on some factors such as signals they receive in and out of the cells, environmental factors, leading to different functions of the cells and the way they look.
.
How many moles of carbon is 1.88 x 1025 carbon atoms?
Answer:
31.23 molesExplanation:
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{1.88 \times {10}^{25} }{6.02 \times {10}^{23} } \\ = 31.229235...[/tex]
We have the final answer as
31.23 molesHope this helps you
Which model shows a way that large molecules can enter a cell without using the cell's energy? Outside the cell O A Cell membrane Vacuole 1 2 Inside the cell В.
Answer:
its B
Explanation:
I took the test and its that passage way thing. (tell me if this works for you! it will but just wanna make sure!)
help me get it right and no links
Answer:
limited
Explanation:
have a good day :)
3. How do we get mass from moles?
A. multiply by Avogadro's number
B. multiply by molar mass
C. divide by Avogadro's number
D. divide by molar mass
How many grams of strontium nitrate (Sr(NO3)2) contain 40 grams of oxygen atoms?
Answer:
88g of Sr(NO3)2 are present
Explanation:
To solve this question we must, as first, find the moles of oxygen. Based on the chemical formula of strontium nitrate, there are 6 atoms of oxygen per mole of strontium nitrate. Thus, we can find the moles of strontium nitrate and its mass as follows:
Moles Oxygen:
40g * (1mol / 16g) = 2.5 moles Oxygen
Moles Strontium nitrate:
2.5 moles Oxygen * (1mol Sr(NO3)2 / 6mol O) = 0.4167 moles Sr(NO3)2
Mass (Molar mass Sr(NO3)2: 211.63g/mol)
0.4167 moles Sr(NO3)2 * (211.63g / mol) =
88g of Sr(NO3)2 are presentA solution has a pH of 8.30. Determine the OH- concentration
Answer:
Explanation:
We know that
pH +pOH = 14
Given pH = 8.30
⇒ p0H = 14-8.30 = 5.70
Since, we know that
[tex]10^{-pH} = [H^{+}][/tex]
Which of the following effect increases the solubility of Ca(OH)2?
O Adding an acidic solution
O Adding KOH
O Adding solid CaCl,
O Adding solid NaOH
O Adding CaCO3
Answer:
adding an acidic solution
Explanation:
Strong acids dissociate completely in water and the H⁺ ions react with the OH⁻ ions to make H₂O. If we add an acid to our solution of Ca(OH)₂, the acid protons would react with some of the OH⁻ ions and drive the equilibrium to the right. More of the solid Ca(OH)₂ should dissolve.
I need help with this question!!
Answer:
Fossil fuels..........
An echo is an example of a sound wave
answers:
A: refracting.
B: reflecting.
C: diffracting.
D: absorbing.
Answer:
B: reflecting
Explanation:
Sound waves can bounce off smooth
PLZZ HELP!!!!!!! What is PH
What is the pH of an HCl solution if [H+] = 0.03?
A. 0.03
B. 1.5
C. 3.0
D. 3.5
Answer: B
Explanation:
1.5 :D
Which describes the titration graph when a strong acid is titrated by a weak base?
It begins at a low pH and has an equivalence point of 7.
It begins at a low pH and has an equivalence point less than 7.
It begins at a high pH and has an equivalence point of 7.
It begins at a high pH and has an equivalence point greater than 7.
Answer:
the answer is b edg 2021
Explanation:
it just is
Use the drop-down menus to identify the class of compounds to which each structure belongs.
The functional groups which are found in the molecules are responsible for their chemical reactions. Here the first organic compound is an acid, second one is an ether, third one is an alkyl halide and the fourth is an primary amine.
The functional groups in the field of organic chemistry can be defined as the substituent atoms or groups of atoms which are attached to the specific molecules. They have distinct features and properties and they are independent of the molecules they are attached to.
The compound with the functional group R-COOH is acid, R-O-R¹ is ether, R-X and R-NH₂ is a primary amine.
To know more about functional groups, visit;
https://brainly.com/question/29263610
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If an endothermic reaction begins at 26 degrees celsius and decreases by 2 degrees Celsius per minute, how long would it take to get to 0 degrees celsius?
Answer:
It would take 13 minutes.
Explanation:
The temperature decreases at a linear rate, meaning that we can describe the process by using the following formula:
T₂ = T₀ - 2*tWhere T₂ is the final temperature, T₀ is the initial temperature; and t is the elapsed time in minutes.
We input the data given by the problem:
0 °C = 26 °C - 2°C/min * tAnd solve for t:
t = 13 minThis tool is used to measure
Answer:
C. volume
Explanation:
Will give brainliest please help!!
Answer:
D. The energy level of the electron.
Explanation:
There are four quantum numbers which are used to describe the movement and paths or positon of each electron within an atom. Quantum numbers can be used to determine the electronic configuration of atoms and the most likely location of the atom's electrons. Quantum numbers are also used in determining other characteristics of atoms, such as ionization energy and the atomic radius.
The four quantum numbers are namely, principal, azimuthal, magnetic and spin quantum numbers.
Principal quantum numbers are denoted by the symbol ‘n’. They describe the principal electron shell or energy level the atom.The value of the principal quantum number are positive integer values that is equal to or greater than one. The value n = 1 represents the innermost electron shell of an atom, which corresponds to the lowest energy state of an electron. The larger the values of 'n' the greater the energy level and the farther the electron is from the nucleus.
What is the percentage by mass of copper in copper oxide (CuO)?
Answer:
79.89%
Explanation:
Copper has a molar mass of 63.55
Oxygen has a molar mass of 16.00
If you add these you get 79.55
To get the mass percent of copper divide copper by the whole. 63.55/79.55*100= 79.89%
How much 2 M HBr is needed to neutralize 380 mL of 0.1 M NH4OH?
Answer:
19ml
Explanation:
trust me
Can y’all help with question 17
Answer:
7. Option 2. Atom 1 and Atom 4
8. The same number of valence electron
Explanation:
7. Determination of which symbol represent an isotope.
Isotopes are atoms having the same atomic number but different mass number due to the difference in the neutron number.
From the question given above, the following were obtained:
Z => atomic number
A => mass number
Atom >>> Isotope >>>>> Z >>>> A
1 >>>>>>> ¹⁷₇E >>>>>>>> 7 >>>> 17
2 >>>>>>> ¹⁷₈E >>>>>>> 8 >>>> 17
3 >>>>>>> ¹⁸₆E >>>>>>> 6 >>>> 18
4 >>>>>>> ¹⁸₇E >>>>>>> 7 >>>> 18
From the table above, only atom 1 and 4 has the same atomic number. Hence, atom 1 and atom 4 are isotopes.
8. To know the correct answer to the question, we shall write the electronic configuration of magnesium and calcium. This can be obtained as follow:
Mg (12) => 1s² 2s²2p⁶ 3s²
Valence electron => 2
Ca (20) => 1s² 2s²2p⁶ 3s²3p⁶ 4s²
Valence electron => 2
We can see that magnesium and calcium both have the same valence electron. Hence, they will have similar chemical properties.
What is the molecular formula for this molecule? a
Answer:
In a molecular formula, it states the total number of atoms of each element in a molecule.
Explanation:
Mary is standing on a train moving east at 10 km per hour. Alicia is sitting on a train that passes in the opposite direction at 30 km per hour. From Mary's point of view, how fast is Alicia moving?
Help
Given the equation:
Zn + 2HCl → ZnCl2 + H2
How many moles of HCl would be required to
produce a total of 2 moles of H2?
Answer:
4 moles of HCl will be required to produce 2 moles of H2.
Explanation:
A balanced chemical equation gives the stoichiometric ration of moles of reactants required to produce a certain number of moles of products. The ratio of moles of reactants to moles of products is known as the mole ratio and is constant for a given chemical reaction.
In the given balanced equation of reaction shown below:
Zn + 2HCl → ZnCl2 + H2
The mole ratio of HCl and H2 is 2:1. This means that in this reaction between Zinc metal and hydrochoric acid to produc zinc chloride and hydrogen gas, every two moles of hydrochloric acid used in the reaction will result in the production of one mole of hydrogen gas.
Therefore for two moles of H2 to be obtained from the reaction, twice the number of moles of HCl is required.
Moles of HCl required = 2 × 2 moles = 4 moles of HCl.
What is the standard cell notation of a galvanic cell made with zinc and gold?
A. Zn2+(aq) | Zn(s) || Au(s) | Au+(aq)
B. Au(s)| Aut(aq) || Zn2+(aq) | Zn(s)
C. Aut (aq)| Au(s) || Zn(s) | Zn2+(aq)
D. Zn(s) | Zn2+ (aq) || Aut(aq) | Au(s)
Answer:
D
Explanation:
What is reproduction?
2 C5H5 + Fe = Fe(C5H5)2
May someone assist, please...? I don't know how to do chemistry work...
1) How many mL of 5.00M CaSO4 solution must be
diluted with water to prepare 500.0 mL of 0.900M CaSO4?
2) 20.0 mL of a stock solution of NaOH is diluted with water to prepare 150.0mL of 1.50 M NaOH solution.
Calculate the Molarity of the stock NaOH solution?
3) 12.00 mL of 3.50 M NaOH solution is diluted with 88.0 mL of water.
What is the concentration of sodium hydroxide in the diluted solution?
4) 9.0 mL of 8.0 M HCl solution is diluted with water to prepare 0.50 M HCl solution. What is the final volume of this solution?
Answer:
1) 90.0 mL
2) 11.25 M
3) 0.477 M
4) 144 mL
Explanation:
The main formula that will be used for all these calculations is:
C₁V₁ = C₂V₂
C stands for concentration and V stands for volume and the subscripts 1 and 2 indicate an initial concentration or volume and a final concentration or volume.
For each problem, it's best to start by figuring out what you have and what you need to find. Figure out if you're looking for an initial value or a final value.
1) We need to find the initial volume. So, take what values you have and plug them in and then solve for whatever variable:
5.00 M · V₁ = 500.0mL · 0.900 M - divide by 5.00
C₁ = 90.0 mL
2) This time we're finding the initial concentration:
20.0mL · C₁ = 150.0mL · 1.50 M - divide by 20.0mL
C₂ = 11.25 M
3) Now we're finding the final concentration:
12.00mL · 3.50 M = 88.0mL · C₂ - divide by 88.0mL
C₂ = 0.477 M
4) Finally, we're looking for the final volume:
9.0mL · 8.0 M = 0.50 M · V₂ - divide by 0.50 M
V₂ = 144mL
who discovered electron
Answer: Electricity
Answer:
J.J Thomas in 1897
What is the source of solar energy? electricity . solar panels the sun None of the above
Answer:
The Sun
Explanation:
Solar power is energy from the sun that is converted into thermal or electrical energy.
Answer:
The sun
Explanation:
The sun is the main source of solar energy.
1. Which is true for any element?
A. Atomic number = number of protons + number of electrons
B. Atomic number = nun number of protons
C. Atomic number = number of protons + number of neutrons
D. Atomic number = nun number of protons, electrons, and neutrons
1. How many grams of NaOH are needed to react with two moles of H2SO4? 2NaOH + H2SO4 Na2SO4 + 2H20
Explanation:
Explanation:
Given the molecular weights:
M
r
N
a
O
H
=
40
g
m
o
l
M
r
N
a
2
S
O
4
=
142
g
m
o
l
The analogy of the moles will be held constant:
n
N
a
O
H
n
N
a
2
S
O
4
=
2
1
n
N
a
O
H
n
N
a
2
S
O
4
=
2
For each one, substitute:
n
=
m
M
r
Therefore:
n
N
a
O
H
n
N
a
2
S
O
4
=
2
m
N
a
O
H
M
r
N
a
O
H
m
N
a
2
S
O
4
M
r
N
a
2
S
O
4
=
2
200
40
x
142
=
2
200
⋅
142
40
x
=
2
200
⋅
142
=
2
⋅
40
x
x
=
200
⋅
142
2
⋅
40
=
100
⋅
142
40
=
10
⋅
142
4
=
1420
4
=
=
710
2
=
355
g
r
a
m
s
(or just use a calculator
11 The cross section compares the densities of different Earth layers. Which Earth layer is most dense?
Answer:
b
Explanation:
i took the quiz