Answer:
the answer is that a physical change is easier to reverse then a chemical change.
Explanation: In order for a physical change to take place it's easier to just undo what happened then if it was a chemical change because in order for very few chemical changes to reverse to it's original substance you would need another chemical change.
In preschool, students have the current exchange system for toys: 4 orange blocks = 5 stickers
7 stickers = 2 toy soldiers
3 toy soldiers = 6 dinosaurs
How many dinosaurs (dino) will a student get if they have 16 orange blocks?
Answer:
11
Explanation:
16 orange blocks = 4*5stickers
20 stickers=20*2/7 toy soldiers =40/7 toy soldiers
40/7 toy soldiers=40/7*6/3 dinosaurs =40*2/7=80/7 =11.43 ~~ 11 dinosaurs
6. A sheet of metal is 2 cm wide, 10 cm tall, and 15 cm long. It was 4 grams. What is the
density?
Answer:
0.013g/cm^3
Explanation:
density= mass÷volume
Answer:
0.01(3) g/cm3 (cm3 means centimeter cubed, (3) means the 3 goes on forever)
Explanation:
The volume of the sheet is 300 cm3, and dividing 4 grams by 300 cm3 gets you 0.01(3) g/cm3. Hope it helps!
why people on earth cannot see the entire shape of the milky way
Answer:
Explanation:
That is because the Milkyway is full of dust and gas, you cannot really see something if it has dust and gas
Answer:
Its too far away to see
Explanation:
You would probably have to be in space
What is the charge on an electron? -1 0 +1 +2
Answer:
to be honest I don't know
Explanation:
my brain won't work with this
*
new
The process of wave erosion is a relatively
phenomenon on Earth.
10 points
о
True
о
False
The answer fam is......... False
Compounds have different properties than the elements they are made from because
A . They are produced from a chemical change . B. They are produced by a physical change. C. A new substance is not made . D. Smoke , change or color, production of gas does not occur during the process.
Answer:
D
Explanation:
An object with a mass of 1.2 g takes up a space of 2.4 mL. What is it's density?
Answer:
The answer is 0.5 g/mLExplanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\ [/tex]
From the question we have
[tex]density = \frac{1.2}{2.4} \\ [/tex]
We have the final answer as
0.5 g/mL.Hope this helps you
How many moles are in a sample of 2.39 x 10^23 atoms of sodium (Na)
Answer:
The answer is 0.4 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
From the question we have
[tex]n = \frac{2.39 \times {10}^{23} }{6.02 \times {10}^{23} } \\ = 0.39700996...[/tex]
We have the final answer as
0.4 molesHope this helps you
Which of the following statements is true?
a) Carbon dioxide is easier to compress than water.
b) Plasma is made of free electrons, ions, and neutral atoms.
c) Bose-Einstein condensates form at very cold temperatures.
d) All of the above.
Answer:
All of the above
Explanation:
I know about the first two choices but not so much about the last one
Determine the number of moles of 725.0 g of BaSO4
Answer:
It would be 3.1063937724731447 moles.
Hope this helps :)
The Following do not need sun's energy EXCEPT
a. rotating clock
b. evening torch
c. plowing man
d. winding stairways
How many moles of Al are there in 20g of Al2(C2O4)3?
A piece of metal that has a density of 5.2 g/cm3 and a mass of 100 g was placed in a full jar of water. How many mL of water was spilled out of the jar? Note: one cm^3 = one mL
Answer:
100g / (5.2g/cm3)
= 100g / (5.2g / 1cm3)
= 100g x 1cm3 / 5.2 g
= 19.2 cm3
Since 1 cm3 = 1 ml, your answer is 19.2 ml.
The given density and mass of the metallic piece can be used to estimate the volume of the substance. The metal with a mass of 100 gm and a density of 5.2 g/cm³ has a volume of 19.23 ml.
What is the relation between density and volume?The density of the substance has been given by the ratio of mass to the volume of the substance in g/cm³ or g/mL. It shows the packaging of the molecules in the substances and has been in inverse relation to the volume.
The mass being constant and an increase in volume decreases the density of the substance and vice versa. The volume can be calculated as:
Volume = mass ÷ density
Given,
Density of the metal (ρ) = 5.2g/cm³
Mass of the metal piece (m) = 100g
Volume = V
Substituting the values above as:
ρ = m ÷ V
V = m ÷ ρ
V = 100 ÷ 5.2
= 19.23 mL
Therefore, 19.23 mL is the volume of water that spilled out of the jar.
Learn more about volume and density, here:
https://brainly.com/question/13799762
#SPJ2
what unit of measure would i use to measure the width of my fingernail A millimeters
B centimeters C meters D kilometers
E grams
what is the name of CCI3
carbon trichlorine????
Carbon tetrachloride, also known by many other names (such as tetrachloromethane, also recognised by the IUPAC, carbon tet in the cleaning industry, Halon-104 in firefighting, and Refrigerant-10 in HVACR) is an organic compound with the chemical formula CCl4.
The missing components in the table to the right
are indicated with orange letters. Complete the
table by filling in the corresponding number(s) or
symbol(s) below.
A
B
1111
С
D
E
F
G
The Atomic Number (Z) indicates the number of protons in an atom of an element. If the atom is neutral then the number of protons will be equal to the number of electrons. So the atomic number can also indicate the number of electrons.
Mass Number (A) = Number of protons + Number of Neutrons
Atomic Number (Z) = Mass Number (A) - Number of Neutrons
Atomic number = number of protons = number of electrons ⇒ neutral atoms
Atomic number - positive charge = number of electrons ⇒ cation
Atomic number + negative charge = number of electrons ⇒ anion
You can also see the periodic system
A. Indium (In)
B. proton = electron = 27
C. proton = electron = 73
D. proton = electron = 49
E=F. atomic mass - neutron = 137 - 81 = 56
G. atomic mass-proton = 115- 49 = 66
H. 181-73 = 108
Answer:
I know I´m kinda late but....
Explanation:
A. In
B. 27
C. 73
D. 49
E. 56
F. 54
G. 66
H. 108
I. 32
What is the specific location water is in during each state of matter
If an animal is placed into a sealed container for a short time, the oxygen level will
A. decrease and the carbon dioxide level will increase.
B. decrease and the carbon dioxide level will decrease,
C, increase and the carbon dioxide level will increase.
D. decrease and the carbon dioxide level will stay the same.
E increase and the carbon dioxide level will decrease.
Answer:
A
Explanation:
Animals take in oxygen and convert it into carbon dioxide therefore the oxygen levels will decrease and the carbon dioxide levels will increase
If an animal is placed into a sealed container for a short time, the oxygen level will: decrease and the carbon dioxide level will increase.
What happens to oxygen level inside a container:The oxygen held inside the space is quickly being consumed by the freight or because of rusting inside a space, and that encased spaces must consistently be treated as perilous. And the carbon dioxide levels on the other hand will increase.
It will not take a long time for an animal to survive under these conditions.
Thus. option A is correct.
Find more information about Oxygen here:
brainly.com/question/26073928
Identify the mineral that can have the composition of KMg3AlSi3O10(OH)2
Answer:
Phlogopite
Explanation:
It is a member of mica group family of phyllosilicates mineral. It is the magnesium endmember of the biotite stable - the chemical formulation KMg3AlSi3O10 (F, OH) 2.
what is the mass of 10 moles of helium
Answer:
The mass of 10 moles of helium is: 2.5
The graph above compares three states of a substance.
Which of the following choices would NOT be an appropriate label for the y-axis?
A. motion of particles.
B. density of particles.
C. randomness of particles.
D. kinetic energy of particles.
Answer: is C
Explanation:
What solution turns litmus paper red?
A. acidic
B. neutral
C. none
D. basic
Answer:
The answer is A please mark brainliest
Explanation:
Why are the coefficients before a chemical symbol important?F. They show the number of elements in each molecule.G. They indicate the number of molecules of each substance.H. They describe the number of times each molecule reacts.J. They explain the order in which the reaction takes place
Answer:They indicate the number of molecules of each substance
Explanation:
When we write chemical reaction equations, we usually put a number before the symbol of each reactant.
These coefficient shows the number of molecules of that specie that is involved in the balanced reaction equation for the reaction.
These coefficients are important because they are used in carrying out stoichiometric calculations.
what is 1.23 x 10^-3 in standard notation
Answer:
=0.00123
Explanation:
Look at the attachments below
Hope this helps (:
Answer:
0.00123
Explanation:
Standard notation is the normal way of writing numbers. Examples include 1, 2, and 10. The number 1.23 x 10^-3 is written in scientific notation. The decimal goes after the first nonzero integer and it is multiplied by a power of 10. The power or exponent attached to the 10 tells you how many places over you need to move the decimal to get back into scientific notation. Examples include 1.00 x 10^2 (representing 100 in standard form because you would move the decimal two places to the right.), 2.0 x 10^1 (representing 20 in standard form because you would move the decimal one place to the right), and 3.0 x 10^-4 (representing 0.0003 in standard form because you would move the decimal four places to the left since it is a negative exponent).
The negative (-3) exponent in 1.23 x 10^-3 indicated to move the decimal three places to the left. If it was positive, you would move it three places to the right.
In 1.23 x 10^-3 move the decimal to the left 1 place to get:
0.123
two places to get:
0.0123
and a third place to get:
0.00123
The final answer is 0.00123
Volcanic belts form along
a.
islands in the Pacific Ocean.
b.
North American mountain ranges.
c.
the boundaries of Earth’s plates.
d.
the coast of Antarctica.
Please select the best answer from the choices provided
can you help me with percent abundance??
Percent abundance is the percentage of all the different isotopes of an element and is used to calculate the average atomic mass. For example 99.98% of all Hydrogen in the universe is [tex]^1H[/tex] meaning hydrogen with 1 proton and 0 neutrons while the remaining 0.02% is [tex]^2H[/tex] meaning that [tex]^1H[/tex] is the most abundant by percent.
How does pentane and butane differ from each other
Answer:
Butane has only two isomers and pentane has just three, but some hydrocarbons have many more isomers than these. As you increase the number of carbon atoms in a hydrocarbon, the number of isomers quickly increases.
Please Helpp
Which organelle is correctly matched with the cell process it performs?
A Vacuole — photosynthesis in plant leaf tissue
B Chloroplast — water storage in plant leaf tissue
C Mitochondria — energy production in plant and animal tissue
D Cell wall — supporting the cell in animal tissue
Answer:
Mitochondria - energy production in plant and animal tissue
Explanation:
The mitochondria is the power house of a cell. it contains adenosine-tri- phosphate or ATP molecules that produce energy through active transport. The mitochondria is responsible for energy production in both plant and animal cells
NEED HELP ASAP WITH THESE QUESTIONS GIVING FAIR AMOUNT OF POINTS IF HELPED WITH ALL QUESTIONS Violet light has a wavelength of 4.20 x 10-12 m. What is the frequency?
3. A photon has a frequency (n) of 3.468 x 106 Hz. Calculate its energy
Calculate the energy (E) and wavelength (l) of a photon of light with a frequency of 4.215 x 1014 Hz.
Calculate the frequency and the energy of blue light that has a wavelength of 400 nm
(h = 6.62 x 10-34 J-s).
Calculate the wavelength and energy of light that has a frequency of 9.5 x 1015 Hz.
A photon of light has a wavelength of 0.090 cm. Calculate its energy.
Calculate the energy and frequency of red light having a wavelength of 2.80 x 10-5 cm.
Calculate the energy (E) and wavelength (l) of a photon of light with a frequency of 5.165 x 1014 Hz.
The wavelength of green light from a traffic signal is centered at 7.20 x 10-5 cm. Calculate the frequency.
If it takes 1.56 seconds for radio waves (which travel at the speed of light) to reach the moon from Earth, how far away is the moon?
Calculate the frequency of light that has a wavelength of 4.20 x 10-9m. Identify the type of electromagnetic radiation.
Answer:
a) 7.14e19 Hz
b) 2.298e-27 J
c) 2.793e-19 J; 7.117e9 nm
d) 7.5e14 Hz; 4.96e-19 J
e) 6.2947e-18 J; 31.6 nm
f) 2.21e-22 J
g) 7.1e-19 J; 1.1e15 Hz
h) 3.422e-19 J; 581 nm
i) 4.2e14 Hz
j) 1.92e8 m
k) 7.14e16 Hz; Ultraviolet
Explanation:
Frequency: ν Wavelength: λ Energy: E Speed of light: C (3.00e8) Planck's Constant: h (6.626e-34)
ν -> λ λ = C/ν
λ -> ν ν = C/λ
For either of these equations, wavelength must be converted to meters or nanometers, depending on the equation.
For ν -> λ, after doing the equation, convert the wavelength into nanometers by dividing by 1e-9.
For converting λ -> ν, convert the wavelength into meters by multiplying by 1e-9.
For energy: E = hν = hc/λ
Now that the setup is out of the way:
a) Violet light has a wavelength of 4.20 x 10-12 m. What is the frequency?
λ -> ν ν = C/λ
[tex]\frac{3.00e8}{4.20e-12}[/tex] = 7.14e19 Hz
b) A photon has a frequency (n) of 3.468 x 106 Hz. Calculate its energy
E = hν = hc/λ
(6.626e-34) (3.468e6) = 2.298e-27 J
c) Calculate the energy (E) and wavelength (l) of a photon of light with a frequency of 4.215 x 1014 Hz.
E = hν = hc/λ
(6.626e-34) (4.215e14) = 2.793e-19 J
ν -> λ λ = C/ν
[tex]\frac{3.00e8}{4.215e14}[/tex] = 7.117 m
[tex]\frac{7.117m}{1}*\frac{1nm}{1e-9m}[/tex] = 7.117e9 nm
d) Calculate the frequency and the energy of blue light that has a wavelength of 400 nm (h = 6.62 x 10-34 J-s).
λ -> ν ν = C/λ
[tex]\frac{400 nm}{1} *\frac{1e-9m}{1nm}[/tex] = 4e-7 m
[tex]\frac{3.00e8}{4e-7}[/tex] = 7.5e14 Hz
E = hν = hc/λ
(6.626e-34) (7.5e14) = 4.96e-19 J
e) Calculate the wavelength and energy of light that has a frequency of 9.5 x 1015 Hz.
ν -> λ λ = C/ν
[tex]\frac{3.00e8}{9.5e15}[/tex] = 3.16e-8 m
[tex]\frac{3.16e-8m}{1}*\frac{1nm}{1e-9m}[/tex] = 31.6 nm
E = hν = hc/λ
(6.626e-34) (9.5e15) = 6.2947e-18 J
f) A photon of light has a wavelength of 0.090 cm. Calculate its energy.
E = hν = hc/λ
Convert the wavelength from cm to meters:
[tex]\frac{0.090cm}{1} *\frac{1m}{100cm}[/tex] = 9e-4 m
[tex]\frac{(6.626e-34)(3.00e8)}{9e-4}[/tex] = 2.21e-22 J
g) Calculate the energy and frequency of red light having a wavelength of 2.80 x 10-5 cm.
E = hν = hc/λ
Convert the wavelength from cm to meters:
[tex]\frac{2.80e-5cm}{1} *\frac{1m}{100cm}[/tex] = 2.8e-7 m
[tex]\frac{(6.626e-34)(3.00e8)}{2.8e-7}[/tex] = 7.1e-19 J
λ -> ν ν = C/λ
Convert the wavelength from cm to meters:
[tex]\frac{2.80e-5cm}{1} *\frac{1m}{100cm}[/tex] = 2.8e-7 m
[tex]\frac{3.00e8}{2.8e-7}[/tex] = 1.1e15 Hz
h) Calculate the energy (E) and wavelength (l) of a photon of light with a frequency of 5.165 x 1014 Hz.
E = hν = hc/λ
(6.626e-34) (5.165e14) = 3.422e-19 J
ν -> λ λ = C/ν
[tex]\frac{3.00e8}{5.165e14}[/tex] = 5.81e-7 m
[tex]\frac{5.81e-7m}{1}*\frac{1nm}{1e-9m}[/tex] = 581 nm
i) The wavelength of green light from a traffic signal is centered at 7.20 x 10-5 cm. Calculate the frequency.
λ -> ν ν = C/λ
Convert the wavelength from cm to meters:
[tex]\frac{7.20e-5 cm}{1} *\frac{1m}{100cm}[/tex] = 7.2e-7 m
[tex]\frac{3.00e8}{7.2e-7}[/tex] = 4.2e14 Hz
j) If it takes 1.56 seconds for radio waves (which travel at the speed of light) to reach the moon from Earth, how far away is the moon?
All we want to do here is to convert frequency (speed) to wavelength (distance). This problem requires a bit of thought, but it isn't bad once you realize that frquency is speed and wavelength is distance. It becomes just like the other problems after that. Also, I'll leave this distance in meters, but I think you can figure out how to convert it if it wants it in another unit.
One second is equal to 1 Hertz, so our frequency is 1.56 Hz.
ν -> λ λ = C/ν
[tex]\frac{3.00e8}{1.56}[/tex] = 1.92e8 m
The actual distance from the earth to the moon via google is 3.84e7, but sometimes problems like this will mess with the numbers to make sure that you didn't just look up the answer. I'm still pretty sure that this is right, however.
k) Calculate the frequency of light that has a wavelength of 4.20 x 10-9m. Identify the type of electromagnetic radiation.
First, we convert wavelength to frequency, as normal:
λ -> ν ν = C/λ
[tex]\frac{3.00e8}{4.20e-9}[/tex] = 7.14e16 Hz
Then we identify the electromagnetic wave type. You can look up a conversion chart for these on google, but since our frequency is in the e15 - e17 range, this light is considered ultraviolet.
2. When one plate is thrust under another plate it will create what landform?
a. Rift valley
b. Mountain range
C. Subduction zone-trench
d. Crater
Answer:
a
Explanation: