93. Coke is an impure form of carbon that is often used in the
industrial production of metals from their oxides. If a sam.
ple of coke is 95% carbon by mass, determine the mass of
coke needed to react completely with 1.0 ton of copper(II)
oxide.
2CuO(s) + C(s) → 2Cu(s) + CO2(8)
Answer:
Explanation:
A cubic container is filled up with an unknown liquid whose density is 0.180 g/cm3. The side lengh of the container is 5.00cm. Whaf is the mass of this liquid??
Answer:
THE MASS OF THE LIQUID IS 22.5 g
Explanation:
Density = 0.180 g/cm3
Side length = 5 cm
Mass = unknown
To calculate the mass of the liquid, we use the formula:
Mass = density * volume
Volume of a cube or cuboid container = l^3
Volume = 5 ^3 = 125 cm3
So therefore, the mass of the liquid is:
Mass = 0.180 * 125
Mass = 22.5 g
In conclusion, the mass of the liquid in the container is 22.5 g
0.000000000008
Scientific notation
Answer:
= 0.8
not really sure about the answer I just guessed it
am sorry if it's wrong
The pressure of a basketball is 412 mmHg. How many kPa is that equal to?
a. 313, 000 kPa
b. 0.117 kPa
c. 0.542 kPa
d. 54.9 kPa
Answer:
d. 54.9 kPa
Explanation:
mmHg and Pa are units of pressure used in chemistry principally in the study of gases. 1mmHg is equal to 133.322Pa. 412mmHg are:
412 mmHg * (133.322Pa / 1mmHg) = 54929 Pa
The prefix K (Kilo) represents one thousand of the determined unit.
54929Pa are:
54929Pa * (1KPa / 1000Pa) = 54.9kPa
Right answer is:
d. 54.9 kPaDecide which element probably forms a compound with hydrogen that has a chemical formula most and least similar to the chemical formula of the compound formed by hydrogen and selenium.
Answer:
Sulphur
Explanation:
Hydrogen sulphide
Chemical formula: [tex]H_{2} S[/tex]
Oxidation states: +1 and -2
Hydrogen selenide
Chemical formula: [tex]H_{2} Se[/tex]
Oxidation states : +1 and -2
Hope you found this helpful.
3.643 x 10^-1 scientific notation
Answer:
its already in scientific form
its ordinary form would be 0.3643 and dragging the decimal point after the first non zero digit and multiplying it with a multiple of 10 we gain scientific form i-e 3.643*10^-1
Explanation:
In a double-blind test, the non-control group receives a
Answer:
Hi There! I'm new so I hope I get This Right! ^^
Explanation:
double blind test. the control group receives a placebo. Why is a placebo used in a double-blind test? so that the effects on people in two different groups can be compared.
happy To Help! ^^
15 points
Use the Periodic Table to determine the number of PROTONS for the
element: Magnesium, Mg (Atomic # 12). Only include the number in your
answer
Answer:
The number of proton of magnisium = 12
How many significant figures are in 0.0034 cm? a 2 b 3 c 1 d 4
Answer:
A. 2 sig figs
Explanation:
In the number 0.0034, the zeros are called leading zeros. The only function of leading zeros is to fix the decimal point. Leading zeros are not counted as significant figures.
Nickel-63 has a half life of 92 hours. If a
1000 gram sample decayed for 368 hours,
how much Nickel-63 remains?
Answer:
6.25 g of nickel -63 will be left
Explanation:
true or false a measurement must include a unit
HI :)
True
Hope this helps :)
what does code zero mean in a science lab
Answer:
either expolshion or hide
Explanation:
so be ware :O
New substances are produced by a(n)
change.
Answer:
New substances are produced by a chemical change
What is the mass of 7 x 10^28 atoms of Fe?
Answer:
6 x 10⁶ g Fe
Explanation:
Step 1: Set up dimensional analysis
7 x 10²⁸ atoms Fe (1 mol Fe/6.02 x 10²³ atoms Fe)(55.85 g Fe/1 mol Fe)
Step 2: Multiply, divide, and cancel out units
atoms Fe and atoms Fe cancel out.
mol Fe and mol Fe cancel out.
We should be left with g Fe.
7 x 10²⁸/6.02 x 10²³ = 116279 mol Fe
116279(55.85) = 6.49 x 10⁶ g Fe
Step 3: Sig figs
There is only 1 sig fig in this problem.
6.49 x 10⁶ g Fe ≈ 6 x 10⁶ g Fe
Convert 538.35 to scientific notation.
Answer:
= 5.3835 × 102
Explanation:
Answer:
5.3835x10^2
Explanation:
5.3835x10^2
5.3835x100
538.35
When writing a scientific notation, the two numbers in which the decimal is put must be 1-10.
A decimal can't be put between 0-10.
Hope this helps ;) ❤❤❤
5. Water is known to have a composition which is 88.8% oxygen by mass. If you had a
sample of water with a total mass of 367g how many grams of that would be from
hydrogen?
All of the above
10 points
A gardener wants to know how much fertilizer his roses require to have
lots of blooms. Which group would be the control group*
O The plants without any fertilizer.
2 drops of fertilizer
4 drops of fertilizer
None of the above
Yosemite Falls, in California, has a total height of 73,000cm. What is the height in meters?
Answer:
Height in meters = 73000 ÷ 100
(1m =100cm)
= 730m
Hope it helps.
Answer:
730m
Explanation:
100cm = 1m
73,000cm = 73000cm/100cm (take 2 zeros away)
= 730m
ANSWER ASAP PLEASE WILL GIVE POINTS
Which sentence about particles in matter is true?
A. Atoms are present in solids and liquids but not in gases.
B
The particles of matter are in constant motion,
c.
The same kinds of atoms are found in different elements.
D
When a solid changes to a liquid, the sizes of the particles change.
Answer:
b
Explanation:
.
Which of these would most likely be considered a pure substance?
a. Tap water
b. Red Bull
c. Water vapor
d. The air we breathe
e. A rock from your backyard
Answer:
c. Water Vapour
Hope it helps.
the answer is C- water vapour
What could happen if people do not fulfill a civic duty or responsibility
Answer:
While U.S. citizenship provides many rights, it also involves many responsibilities. Civic duties ensure that democratic values written into the Constitution and the Bill of Rights are upheld. Responsibilities include both those that are voluntary as well as those required by law.
Explanation:
If people do not fulfill their civic duties/responsibilities their will be disorderliness in a country. In could result in many bad situations.
Some examples of civic duties are:
paying the taxesabiding by the lawsetc.If people do not pay the taxes it will be a crash-down in the economy of a country.
Voilating the laws will make the country go curropt.
what are thermosetting plastics???
Explanation:
Thermosetting plastic are made up of long chain of molecules which are cross-linked and can be moulded into different shape and size.
Answer:
Hey!
THERMOSETTING PLASTICS are plastics or polymers that become IRREVESIBLY SET/RIGID when it has been heated and cooled...
Explanation:
This means that if you heat up a thermosetting plastic, you only have one chance to mould it or shape it before it cools down...if not you cannot correct this and will have to start again! Which WILL be sad!
AKA : THERMOSET
HOPE THIS HELPS!!
This was on my digital worksheet. I need help, I haven’t used Brainly in a while.
Which statement is correct?
A. Block A has the greatest density.
B. Block B had the greatest density.
C. The density of Block A is equal to the density of Block B.
D. The density of Block B is equal to the density of Block C.
Answer:
Block B
Explanation:
the quantity of mass per unit volume of a substance
even though they have all the same volume, block B is more compact hence the weight is more heavier.
Hydrogen (h) atoms have one electron and exist as diatomic molecules (h2). Helium atoms have 2 electrons and exist only as a single helium atom. Explain why they differ in this way
Answer:
Explanation:
Hydrogen atoms have an electronic configuration of 1s¹. This indicates that they require one more additional hydrogen in order to complete it octet structure and before they can form a reaction.
Helium have an electronic configuration of 1s², which is a noble gas. In noble gas, their octet structures are complete. As such they do not require additional electron before they can form a reaction.
A group of scientists in Alaska notices that not only have atmospheric CO2 levels increased at their sampling site but so too have methane levels. What could account for this increase in methane levels
Answer:
The release of methane from thawed permafrost.
Explanation:
The complete question is
A group of scientists in Alaska notices that not only have atmospheric CO2 levels increased at their sampling site but so too have methane levels. What could account for this increase in methane levels?
- None of the answer options is correct.
- The release of methane from thawed permafrost.
-A decrease in beef production near the researchers' sampling area.
-The melting of permafrost accompanied by the thawing of methane-producing bacteria.
-The failure of rice paddies to be established in Alaska, given its climate.
Permafrost regions like the arctic circle hold a large supply supply of methane in their soils and their seas. Ordinarily, this methane should be gradually released naturally over a long period of time, but the effects of global warming is making these permafrost to thaw at a much faster rate, accelerating the release of methane into the atmosphere. The dark side is that methane is about 80 times more deadly when compared to CO2 in its contribution to the green house effect on earth.
Rule #1: All nonzero digits are significant
#1-9 are significant
Determine the number of sig figs in each of the examples
below.
6782
26.2
.3491
55
Answer:
6782 has 4, 26.2 has 3, 0.3491 has 4 and 55 has 2 significant figures .
Which of these statements best describes how scientific ideas change? a. New evidence leads to the modification of ideas. b. As a scientific idea changes, it eventually becomes a scientific theory and, ultimately, a law. c. Scientific ideas rarely change because they are based on extensive evidence. d. Scientists form opinions based on evidence and decide how the idea should change.
Answer: I think is A
Explanation:
what are the major difference between potential and kinetic energy?
Answer:
The energy of a body or a system with respect to the motion of the body or of the particles in the system. Potential energy is the stored energy in an object or system because of its position or configuration. Kinetic energy of an object is relative to other moving and stationary objects in its immediate environment.
how many pascals are in 41.65 kilopascals?
Answer: 41,650
Explanation: A kilopascal is one thousand pascals, so 41.65 times 1000 equals 41,650
Match each term to its definition. 1. compound 2. atom 3. element 4. molecule a. the basic unit of matter b. a substance containing only one type of atom c. a substance that contains more than one atom d. a material made up of atoms of different elements
Answer:
1. C
2. A
3. B
4. D
i think
Answer:1. compound = c. a substance that contains more than one atom
2. atom=a. the basic unit of matter
3. element=b. a substance containing only one type of atom
4. molecule =d. a material made up of atoms of different elements