Answer: A. Kinetic energy increases during exothermic changes and decreases during endothermic changes
Explanation: During an exothermic change potential energy is converted to kinetic energy. I hope this is correct. :)
Answer:
C
Explanation:
A limited number of the many known elements comprise the largest portion of living matter. Group Elements A Calcium, Phosphorus, Oxygen, Sulfur B Cobalt, Hydrogen, Oxygen, Nitrogen C с Helium, Oxygen, Sulfur, Carbon Hydrogen, Oxygen, Nitrogen, Carbon 1 1 Which group of elements above comprises the largest portion of living matter? A Group A B Group B C Group C D Group D
Answer:
Explanation:
Hydrogen oxygen nitrogen and carbon
Magnesium has a density of 1.738 g/cmº at 25°C. What is the mass of a block of
magnesium that has a volume of 743 cm??
Answer:
87.50g(1cm^3/1.1738g)=50.345 cm^3
Explanation:
volume units id in cubic centimeters
A piece of iron has a density of 7.87 grams per milliliters. It has a mass of 78.7 grams. What is the volume of the piece of iron?
punnet squares, help how do I do this
Explanation:
Im not sure what the other trait is so I couldn't do phenotype. I hope this still helps though
How many moles are I 24.0x10^18 molecules NaOH?
Answer:
[tex] \huge 3.986 \times { 10}^{ - 5} \: \: mol \\ [/tex]
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
From the question we have
[tex]n = \frac{24 \times {10}^{18} }{6.02 \times {10}^{23} } \\ \\ = 3.986 \times { 10}^{ - 5} \: \: mol[/tex]
Hope this helps you
Mass of an empty 50 litres cylinder is 4.8kg. the cylinder is filled with 60atm nitrogen gas. molecular mass of nitrogen is 28. what is the new mass of cylinder
Answer:
8.235 kg
Explanation:
Mass of the cylinder = 4.8 kg
The capacity (volume) of the cylinder = 50 liters
As 1 m^3 = 1000 liters
So, the volume of the cylinder, v= 0.05 m^3
The volume of filled nitrogen, v= 0.05 m^3
Pressure of filled nitrogen, p = 60 atm = 60\times 101325 Pa
Assuming that the nitrogen gas is at room temperature which is 25-degree centigrade,
So, the temperature of nitrogen gas, T=273+25= 298 K
By using the ideal gas equation, pv=nRT
Where n is the number of moles, R is the universal gas constant, R = 8.314 J/mol·K
Putting all the values in the ideal gas equation, we have
(60 x 101325)0.05 = n (8.314) x (298)
n= (60 x 101325 x 0.05)/(8.314 x 298)
n=122.69 moles
As the molar mass of nitrogen is 28, so the total mass of the nitrogen in the cylinder, m= 122.69 x 28 = 3435.32 grams = 3.435 kg.
Hence, the new mass of the cylinder = 4.8+3.435=8.235 kg
the initial internal energy of a system is 43.5kj. it absorbs 8.3kj of heat while performing 3.5kj of work on the surroundings. what is its final internal energy?
Shows works to help me understand what I did wrong.
Answer:
[tex]U_2=48.3kJ[/tex]
Explanation:
Hello!
In this case, since the fist law of thermodynamics helps us to understand how the change in internal energy is defined in terms of the head added to the system and the work done by the system:
[tex]Q+W=\Delta U[/tex]
In such a way, since 8.3 kJ of heat are absorbed by the system, 3.5 kJ are done by the system and the initial internal energy is 43.5 kJ, the final internal energy turns out:
[tex]U_2=U_1+Q-W\\\\U_2=43.5kJ+8.3kJ+3.5kJ\\\\U_2=48.3kJ[/tex]
Best regards!
just write a C.E.R (claim, evidence, reasoning)
Answer:
I have attached pictures below. Maybe those will help?
Explanation:
Answer:
this is a CER model i did for science
Explanation:
claim : Tissue engineering is good for the future and has a positive impact on the future because tissue engineering restores aged, damaged or lost tissues/organs with artificial tissues in a way past medicines or technology has not.
evidence: The infographic states, “This science field provides opportunities for helping many people replace dead or injured organs with new ones. In doing so, it will give them a healthier, more productive life. This field is just beginning, and it is sure to change the length and quality of life of many people in the future.“
reasoning: Many people can benefit from tissue engineering because they can have dead or injured organs replaced with new ones. Tissue engineering is just the beginning and is still being conducted and tested , but as technology gets more advanced and advanced, tissue engineering will improve peoples lives the way medicines and past technology has never done.
In science why is it important to explain why the evidence supports your claim?
A football player kicks a 0.94 kg football with a force of 2.4 N.
Calculate the acceleration of the football as the player kicks the ball. Round your answer to the nearest tenth of a m/s2.
The acceleration of the football is
Explanation:
Fnet = ma
Therefore a = Fnet/m = 2.4N/0.94kg = 2.45m/s².
Answer:
2.6 m/s2
Explanation:
Heeellllpppp ASAP ......
Answer:
I saw B, he vented SUS
Explanation:
Iodoethane Is the answer.
What else is produced when sodium carbonate decomposes?
Na2Co3 - Na2O+
Answer:When a single compound breaks down into two or more compounds or elements in a chemical reaction then it is known as decomposition reaction.
The chemical symbol for sodium carbonate is .
The decomposition of sodium carbonate is:
The decomposition of sodium bicarbonate, will result in the formation of sodium oxide, and carbon dioxide, .
Hence, carbon dioxide, will produce with sodium oxide, on decomposition of .
Explanation:Na2CO3 Na2O +CO2 CO2 is the answer
you have a friend who is using a recipe for flat from american cookbook you notice that he set your over temperature at 175F° what you advise him to do?
Answer:
I will give them advice, that do the power of flame low....
Explanation:
thanks.
What happens to molecular energy(heat) in water when water vapor becomes a liquid?
Group of answer choices
Water vapor gives up heat energy.
Water vapor absorbs heat energy.
As water's mass increases it absorbs energy.
Water vapor retains the same heat energy.
Answer:
Water vapor retains the same heat energy.
Answer:
water vapor gives up heat energy.
Explanation:
Took a quiz and got it right
tide occur in ocean but not in lake why
Answer:
Because while our lakes are Great, they're comparatively much smaller than oceans. And the gravitational pull isn't strong.
A sample is in the second half-life. What percent of the sample is stable at this point?
A. 12.5%
B. 25%
C. 50%
D. 75%
Answer:
75%
Explanation:
on edg :)
Which of the following elements has six valence electrons?
Be
B
C
N
O
What is 797 mm hg to atm?
Answer:
797 mm hg = 1.04868 atm
Explanation:
1 atm = 760 mm hg
797 mm hg to atm is 1.0468 atm
Pressure is defined as the physical force exerted on an object. The force applied is perpendicular to the surface of objects per unit area.
There are many different types of units and prefixes that may be used in general practice to reflect pressure. Thus, it is ensured that all the measurements and their respective units are in the same framework when conducting pressure calculations.
Pascal is the SI unit of pressure, and is the basic pressure unit in the SI (the International System of Units) system.
Given,
Pressure = 797 atm
1 mm Hg = 0.00131579 atm
797 mm Hg = 0.00131579 × 797
= 1.04868 atm
Learn more about Pressure, here:
https://brainly.com/question/30673967
#SPJ1
Which of the following elements in a nonmetal? *
Zinc (Zn)
O Barium (Ba)
Krypton (Kr)
Lithium (Li)
Answer:
Krypton (Kr)
Explanation:
Nonmetals are the elements that have opposing features and characteristics of metals. Nonmetals do not shine and are dull in appearance. They are bad conductors of heat and electricity. They are brittle and cannot be beaten into sheets. The density, melting and boiling points of the nonmetals are low. Krypton (Kr) is a non metal whose atomic number is 36.
A chemical equation is balanced when the
subscripts of the reactants equal the subscripts of the products,
coefficients of the reactants equal the coefficients of the products,
products and reactants are the same chemicals,
same number of each kind of atom appears in the reactants and in the products,
same number of each kind of atom appears in the reactants and in the products
Which element has the highest electronegativity?
Answer:
fluorine
Explanation:
has the highest electronegativity?
How does adding a lone pair affect the position of existing atoms and lone pairs
Answer:
How does adding a lone pair affect the position of existing atoms and lone pairs? It decreases the angles between the atoms - the atoms are moving closer because they are being repelled further away from the lone pairs then they are from the other atoms
Explanation:
hope it helps!
A mixture is prepared using 27.00 mL of a 0.0758 M weak base (pKa=4.594) , 27.00 mL of a 0.0553 M weak acid (pKa=3.235) and 1.00 mL of 1.25×10−4 M HIn and then diluting to 100.0 mL, where HIn is the protonated indicator. The absorbance measured at 550 nm in a 5.000 cm cell was 0.1102 . The molar absorptivity (????) values for HIn and its deprotonated form In− at 550 nm are 2.26×104 M−1cm−1 and 1.53×104 M−1cm−1 , respectively. What is the pH of the solution?
Answer:
pH = 4.164
Explanation:
The first process is to find the initial moles for the base (B) & the acid (HA)
i.e.
[tex]= \dfrac{27 mL \times 0.0758 \ moles \ \ of \ B}{1000 \ mL}[/tex]
[tex]=0.0020466[/tex]
[tex]\simeq 2.047\times 10^{-3} \ moles \ of \ B[/tex]
[tex]= \dfrac{27 mL \times 0.0553 \ moles \ \ of \ HA}{1000 \ mL}[/tex]
[tex]=0.0014931[/tex]
[tex]\simeq 1.493\times 10^{-3} \ moles \ of \ HA[/tex]
The acid with base reaction is expressed as;
HA + B → A⁻ + HB⁺
to 1.493 × 10⁻³ 2.047 × 10⁻³ - -
- 1.493 × 10⁻³ 1.493 × 10⁻³ 1.493 × 10⁻³ 1.493 × 10⁻³
0 5.54 × 10⁻⁴ 1.493 × 10⁻³ 1.493 × 10⁻³
From observation; both the acid & base weak
Given that:
The pKa for base = 4.594
The pKa for acid = 3.235
Recall that;
pKa = -log Ka
So; Ka = [tex]\mathbf{10^{-Ka}}[/tex]
By applying this:
For Base; Ka = [tex]10^{-4.594}[/tex] = 2.5468 × 10⁻⁵
For Acid: Ka = [tex]10^{ -3.235}[/tex] = 5.821 × 10⁻⁴
After the reaction; we have the base with its conjugate acid & conjugate base of acid; Thus, since the conjugate acid of the base possesses a higher value of K, it is likely it would be the one to define the pH of the solution.
By analyzing the system, we have:
HB⁺ + H₂O ↔ B + H₃O⁺
[tex]\dfrac{1.493\times 10^{-3}}{0.1 \ L}[/tex] [tex]\dfrac{5.54\times 10^{-4}}{0.1 \ L}[/tex]
to 0.01493 M 0.00554 M
- x x x
0.01493 - x 0.00554 - x x
Thus;
[tex]2.5468 \times 10^{-5} = \dfrac{(0.00554 -x)\times x}{(0.01493-x)}[/tex]
Using the common ion effect;
0.00554 - x [tex]\simeq[/tex] 0.00554 &
0.01493 - x [tex]\simeq[/tex] 0.01493
∴
[tex]x = \dfrac{2.5468 \times 10^{-5} \times 0.01493}{0.00554}[/tex]
x = [H₃O⁺] = 6.8635 × 10⁻⁵
∴
pH = -log(6.8635 × 10⁻⁵)
pH = 4.164
Your skin is an important organ and has several functions. All of the functions below are performed by the skin EXCEPT
A)
makes vitamin D.
B
prevents-dehydration:
C)
maintains body temperature.
D)
works with bones to help you move.
Answer:D
Explanation:
Your skin makes vitamin D
Your skin prevents dehydration
And your skin maintains body temperature. So you are left with D
Answer:
The correct option is D.
works with bones to help you move
Explanation:
Skin is the outer layer of the body and it is the body's largest organ.
It protect the body from heat and other harmful substances.
It is comprises of three layers;
The Epidermis which is the outer layer.
The dermis which is a fibrous later that protect the Epidermis.
The subcutis is the subcutaneous layer that is beneath the dermis.
Function of the skin.
1. It's regulate body temperature
2. It's protect the body from heat and pathogenic entry.
3. It produces vitamin D
4. The skin allow sensations or feelings of touch, heat, and cold.
Therefore;
works with bones to help you move is wrong because it is the muscle that work with the bone.
How is continental crust different from oceanic crust?
A: Oceanic crust is thicker and more dense.
B: Oceanic crust is thinner and more likely to sink.
C: Continental crust is thicker and more likely to sink.
D: Continental crust is more dense and lighter.
Answer:
b
Explanation:
google lol ur welcome
B: Oceanic crust is thinner and more likely to sink.
HELPPP PLEASEEE
is this
1: radiation
2: conduction
3: convection
This is an example of #2, conduction.
Conduction is the process where heat energy is transmitted through collisions between atoms or molecules.
A biochemist carefully measures the molarity of magnesium ion in of cell growth medium to be . Unfortunately, a careless graduate student forgets to cover the container of growth medium and a substantial amount of the solvent evaporates. The volume of the cell growth medium falls to . Calculate the new molarity of magnesium ion in the cell growth medium. Be sure your answer has the correct number of significant digits.
Answer:
760 uM
Explanation:
A biochemist carefully measures the molarity of magnesium ion in 47, mL of cell growth medium to be 97 uM. Unfortunately, a careless graduate student forgets to cover the container of growth medium and a substantial amount of the solvent evaporates. The volume of the cell growth medium falls to 6.0 mL. Calculate the new molarity of magnesium ion in the cell growth medium Be sure your answer has the correct number of significant digits.
The problem here is that the amount of magnesium ion remains the same irrespective of the volume.
Amount of magnesium in the growth medium = molarity x volume
= 97 x [tex]10^{-6}[/tex] x 47 x [tex]10^{-3}[/tex] = 4.559 x [tex]10^{-6}[/tex]
Then, the volume reduced to 6.0 mL, the new molarity becomes;
molarity = mole/volume
= 4.559 x [tex]10^{-6}[/tex]/6 x [tex]10^{-3}[/tex] = 7.598333 x [tex]10^{-4}[/tex] M = 759.83333 uM
To the correct number of significant digits = 760 uM
Solids, liquids and gases are all
considered to be forms of matter.
Each of these take up space and also
exhibit what other significant
characteristic?
A. color
B. smell
C. texture
B. mass
Answer:
mass
Explanation:
hope this helps you!!
what is the volume of a book that has a width of 10cm,a length that is 2 times the width,and a height that is half the width
width=10cm
length=2xwidth=2x10=20cm
height=width/2=10/2=5
V=w*l*h=10*20*5=1000cm^3
Answer:
1000cm^3
Explanation:
first collect what is known
width 10cm
length 2×width (2×10cm) =20cm
height width/2 (10cm/2) =5cm
now if we use the formula for finding volume of a cuboid that has length, width and height known;
V = l×w×h
= 20cm × 10cm × 5cm
= 1000cm^3
Consider the amino acid below, which is called alanine
Which atoms give the amino acid its unique chemical and physical properties?
A.the CH3 group
B. the amino groups
C. the oxygen atom
D. the hydrogen atom
Answer:
A) the CH3 group
Explanation: