Answer:
c i think
Explanation:
please answer fast! Which of the following statements are false?
A: In a chemical change, atoms are rearranged to make new compounds.
B: The same element is present before and after a chemical change.
C: A physical change does not produce an entirely new substance.
D: A chemical property can be observed without changing the identity of the substance.
I believe it is C.
Hope this helps!
!! brainliest answer !! please help it's due tonight :)
Answer:
3. D
28. also known as Freon 12
Explanation:
how do i word a formal letter to a teacher saying i didn't pay attention during the science lessons and i now have no idea what to do? by the way, this is on edge so i haven't been on a call, or met my teacher in person.
Explanation:
Hello mr/mrs (name) I unfortunately couldn't pay attention to the class due to some issues I had therefore I don't know what we are doing in class
OR
Hello mr/mrs (name) I could understand what we were doing in class I would like it if you could break it down more or explain better to me
OR just say something it had something to do with your internet such as
Hello mr/mrs (name) I didn't understand what you were saying during our class due to some of my internet issues I was have throughout the day. I hope you can explain what we did during the class.
Those may be some of my excuses I've used before
they have worked for me:)
I don't know if that helped?:/
4. Which chemical formula below contains 2
different elements?
A. CO
B. Fe2O3
C. C2H4
D. All of the above
The chemical formula of CO, Fe₂O₃, and C₂H₄ contain atoms of two different elements. Therefore, option (D) is correct.
What is the chemical formula?A chemical formula provides information about the chemical proportions of atoms of each element that are present in a molecule or chemical compound. The chemical formula can be represented by using chemical symbols of elements, numbers (subscripts), and other symbols, such as commas, dashes, brackets, and plus (+) and minus (−) signs.
A chemical formula of a compound has no words but can be written in certain simple chemical structures. Chemical formulae can be more limited in power than chemical names and structural formulae. There are two kinds of chemical formulas in which one empirical formula and another molecular formula.
In the chemical formula of carbon monoxide (CO) has carbon and oxygen two different elements. In the chemical formula of iron oxide (Fe₂O₃) iron and oxygen are two different elements. In the chemical formula of ethane (C₂H₄ ) has carbon and hydrogen two different elements.
Learn more about chemical formula, here:
brainly.com/question/11140581
#SPJ2
What temperature kelvin would .97mol of gas be to occupy 26L at 751.2mmHg?
Answer: 322.56 Kelvin
Explanation:
Use the Ideal Gas Law
[tex]PV=nRT[/tex]
R is the gas constant
T is the temperature in Kelvins
P is the pressure in atmospheres
V is the volume in liters
n is the number of moles of gas
First, the mm of mercury need to be converted to atmospheres using the conversion factor 1atm = 760 torr.
[tex]751.2mmHg (torr) =0.988atm[/tex]
Now plug everything in
[tex](0.988)(26)=(0.97)(0.0821)T\\T=322.56K[/tex]
how many moles are in 5g of Na2CO3?
a) 0.047
b) 1
c) 2
d)21.2
Answer:
0.047
Explanation:
Data : 5g , Na2CO3
Formula:
Molecular mass of Na2Co3 = no.of atomic mass x no. of atom
moles = mass÷ molecular mass
molecular mass = 2(23)+1(12)+3(16)
=106amu
moles = 5÷106
= 0.047 Ans:
advantages of solar energy
PLEASE HURRY IM TIMED Atoms are made up of electrons, neutrons, and____?
protons
compounds
mixtures
water
Answer: protons
Explanation:
A. Protons I learned this in class
Name ways we use technology in inner and outer space
8th grade science btw
Answer:
Explanation:
Many common everyday services such as weather forecasting, remote sensing, satellite navigation systems, satellite television, and some long-distance communications systems critically rely on space infrastructure. ... Of the sciences, astronomy and Earth science benefit from space technology am in 6th grade btw
if a piece of aluminum has a density of 2.7g/cm^3. the mass of 5.2g,what is the volume
Answer:
Gold has a density of 19.3 grams per cubic centimeter, that is, 19.3 g/cm3 or 19.3 g cm-3. Aluminium has a density of 2.7 grams per cubic centimeter, that is, 2.7 g/cm3 or 2.7 g cm-3.
Explanation:
Answer:2.7 g cm-3.
Explanation:Gold has a density of 19.3 grams per cubic centimeter, that is, 19.3 g/cm3 or 19.3 g cm-3. Aluminium has a density of 2.7 grams per cubic centimeter, that is, 2.7 g/cm3 or 2.7 g cm-3.
When a comet enters the solar system, it curves toward the sun. Which statement describes why the sun does not move when a comet is nearby?
Answer:
Explanation:
When a comet enters the solar system it curves towards the Sun due to the Sun's gravitational pull. Every celestial object in the universe has a gravitational pull whose force is dependent on the object's mass. The larger the object is the more gravitational pull it will have. The Sun is the largest object in our Solar system and therefore has the most gravitational pull. This is why the comet curves toward the Sun, but the opposite does not happen because the comet's gravitational pull is not strong enough to pull the Sun.
When elements bond, what is the part of the atom doing the bonding?
Answer:
the valance electrons
Explanation:
Plants respond to different kinds of stimuli. A plant's roots searching for water are an
example of what kind of response?
A. thigmotropism
B. phototropism
C. hydrotropism
D. gravitropism
Answer:
Explanation:
Hydrotropism
Solid iron pellets are heated, melted and drawn into wires. This is an example of a chemical reaction
True
False
Answer:
false
Explanation:
It is a physical reaction because it is being heated.
Answer:
False
Explanation:
Just because the iron was melted into wires does not mean that it isn't iron. It is still iron just in a different form.
1. Which of the following
equalities is false?
A. 1 kilogram = 100 meters
B. 50 milliliters = 5 centiliters
C. 3 grams = 0.003 milligrams
D. 70 hectometers = 7,000 decimeters
3) What are the three types of sedimentary rocks?
Answer:
clastic, organic, and chemical
Which group in the food chain uses the energy of the sun to create its own food A consumers B predators C producers D prey
Answer:
C producers
Explanation:
All food chains start with energy from the sun. This energy is captured by plants. Thus the living part of a food chain always starts with plant life and ends with an animal. Plants are called producers because they are able to use light energy from the sun to produce food (sugar) from carbon dioxide and water.
help please asap. chem sucks
I'm assuming that C is carbon.
[tex]4.590 \: mol \: c \times \frac{12.01 \:g \: c}{1 \: mol \: c} [/tex]
55.1259 g of C
Electrotonic configuration of potassium 19K ion equal the Electrotonic configuration of
1) ⁸0
2) ¹¹Na
3) ¹⁸Ar
4) ¹⁷C1
What is the ratio of the effusion rate of the helium to methane? (round to hundreds)
Answer:
2.00
Explanation:
From Graham's law; the rate of effusion is inversely proportional to the square root of the relative molecular mass.
Let the rate of effusion of Helium be R1
Let the rate of effusion of Methane be R2
Let the molecular mass of Helium be M1
Let the molecular mass of Methane be M2
Hence;
R1/R2 = √M2/M1
R1/R2 = √16.0294/4.0026
R1/R2 = 2.00
(e)
Calculate the mass of one atom of sodium.
Use the equation:
relative atomic mass
mass of one atom of sodium =
Avogadro constant
Avogadro constant = 6.02 x 1023
Give your answer to 2 significant figures
Answer:
3.82 × 10 ^-23 g
Explanation:
6.02 x 10^23atoms = 1 mole of sodium
1 atom = 1/(6.02 x 10^23) mole
mass = mole × molar mass
= 1/(6.02 x 10^23) × 23
= 3.82 × 10 ^-23 g
Can somebody sort these from non-metals to metals?
Sonorous, low melting point, high density, brittle, dull, malleable, basic oxide
Glycerine is viscous than water?why
Answer:
Yes
Explanation:
Why is glycerol more viscous than water?
The glycerine is more viscous than water because due to presence of hydrogen atoms , we all know that glycerine has more hydrogen bonding than water molecule , which makes an aggregation which means that glycerine is more viscous than water , in simple words glycerine can't flow as that of water molecule.
Skill and
Serina is a ballet dancer. During her dance, she dances in a "Z" pattern on the stage. It takes her about 30 seconds to
complete the ®Z." The top and bottom of the "Z" are equal distances of about 3 meters each. The middle part of the "Z"
is about 6 meters long. How quickly (in meters per second) is she traveling during this part of the dance?
Answer:
2.5 m/s
Explanation:
total of 12 meters in 30 seconds
12x2.5=30
Two rabbit species, X and Y, live in an Arctic environment that is also populated by wolves. Species x turns white in the winter and
brown in the spring. Species y stays brown all year. The population of species X has slowly been increasing over the population of
species Y. What is most likely causing this population change?
Answer:
yy
Explanation:
Heeeeeellllppp, Iiiimmm sssooo stttuuuccckkk!
Answer:
I think it would be D. None of the above
Explanation:
why I think this is because none of the answers really adds up to it
How many atoms are in 100g H2O ?
Answer:11
explain
: cause i think it is
I NEED HELP WIT QUESTION THREE
Answer: 2.00
Explanation:
2 rounded to the nearest hundredth is 2.00
your welcome :)
answers for all three:
1. 4.00
2. 16.04
3. 2.00
cell are the blank unit of all living organisms
PLS HELPPPP OMG PLSPLSPLSPLSPLS
Answer:
D 44.8 L liters of hydrogen gas