Answer:
B. Knowing the color and brightness of a star
Explanation:
Problem Page Question A major component of gasoline is octane C8H18. When liquid octane is burned in air it reacts with oxygen O2 gas to produce carbon dioxide gas and water vapor. Calculate the moles of octane needed to produce 2.4mol of water. Be sure your answer has a unit symbol, if necessary, and round it to the correct number of significant digits. 2.4 Clears your work. Undoes your last action. Provides information about entering answers.
Answer:
0.3mol C8H18
Explanation:
For this we must first look at the reaction taking place:
C8H18+O2 --> H2O + CO2
Balancing the equation we get:
2(C8H18)+25(O2) --> 18(H2O) + 16(CO2)
Form there we now need to know how many moles of Octane are needed to produce 2.4moles of H2O. The conversion is as follows:
2.4molH2O ((2mol of C8H18)/(18mol of H2O)) = 0.3mol C8H18
Match each measurement to the correct number of significant figures it contains.
26.000 cm
0.800 km
0.00050 g
7300 m
3 x 10^5 mL
1
2
3
4
5
6
Answer:
Answer: a, b, c, d, e, f. a) 1 significant figure b) 3 significant figures c) 2 significant figures d) 4 significant figures e) 5 significant figures f) 6 significant figures Note that non-integers are rounded to the nearest integer and then count as the number of significant figures. For example, rounding 1.5 to two significant figures would mean one significant figure because it is an integer, not because it is a decimal.
Answer explanation: 26.000 cm = 2.6 x 10^2 cm. 0.800 km = 8 x 10^-3 km. 0.00050 g = 5 x 10^-4 g. 7300 m = 7.3 x 10^2 m. 3 x 10^5 mL = 3000000 ml or 300 L
Explanation:
How many significant figures are in each of these measurements?
32.14 cm
4.34 x 10^3 cm
2 g
13000 L
1.007 g/mL
6 mL
0.000005 L
2.7 mL
Answer: a, b and c contain 7 significant figures and the others each have 4 significant figures.
Incorrect answers indicate incorrect choices made for this problem or other problems on the worksheet . Answer explanation: 32.14 cm = 3.214 x 10^2cm 4.34 x 10^3cm = 4.34x10^5 cm 2 g = 2 grams 13000 L = 13 kiloliters 1.
Why do scientists use models of molecules?
A. To research the known effects of the molecule on the environment
B. To explain how electrons, protons, and neutrons are arranged
C. To show the structure of molecules, which are too small to see
D. To design an experimental setup to synthesize molecules
Answer:
C
Explanation:
9 The relative abundances of the two isotopes of chlorine are shown in this table:
Relative abundance
Isotope
35C1
75%
3701
25%
Use this information to deduce the mass spectrum of chlorine gas
Answer:
35.50 atomic mass
Explanation:
1. Multiplicate each isotope mass by its abundance
35 uma x 75% = 26.25 amu
37.01 uma x 25% = 9.2525 amu
2. Add the values
26.25 + 9.2525 = 35.50 atomic mass
Dissolving salt in water is what kind of reaction
O Endothermic reaction
O Exothermic reaction
O No answer text provided
O No answer text provided
Answer:
endothermic reaction
Explanation:
because salt dissolve water
Answer:
EXOTHERMIC REACTION AS WHEN YOU TOUCH IT YOU WILL FEEL SOME HEAT.
Please help me. I will mark you as a brainleist.
Answer:
Your answer is in the attachment. Hope this helps you. Stay blessed.
who started water conservation in himachal pradesh
Explanation:
There are government khatris as well, which are maintained by the panchayat. Kuhls are a traditional irrigation system in Himachal Pradesh- surface channels diverting water from natural flowing streams (khuds). A typical community kuhl services six to 30 farmers, irrigating an area of about 20 ha.
Which result would support the particle theory of light? Increasing the intensity of the light causes electrons to be ejected. Frequencies of light that fall below the frequency threshold of the metal do not eject electrons. There is a time gap between when light strikes the metal and when electrons are ejected.
Frequencies of light that fall below the frequency threshold if the metal do not eject electrons.
How is gas pressure useful
Answer: Gas pressure is employed in a variety of industrial operations, and it was the catalyst for the industrial revolution. Many industrial machines were powered by steam in the early twentieth century. To heat the water molecules inside massive boilers, wood was burned.
A 1-L soda bottle contains dissolved carbon dioxide gas. Which bottle would have the highest concentration of dissolved gas?
a bottle that is sealed
a bottle that was opened 1 minute ago
a bottle that was opened 1 hour ago
a bottle that was opened 1 day ago
Mark this and return
Answer:
A bottle that is sealed would have the highest concentration.
Explanation:
When you put a gas into a container, the concentration or the amount of mol inside the bottle would be highly concentrated. If you open the bottle, the CO2 would spread outwards and leave the bottle giving more room between each molecule. The longer you open the bottle, the less concentrated the gas will be.
True or false: animals use photosynthesis to make food
Suppose it takes 21 min for 2.4 g of sugar to completely react with another reagent we added to the flask. What would the reaction rate be
please help me it's urgent
Answer:
save my photo
who knows you might like it :>
An explanation for a broad of observation, facts, and tested hypothses is called a
Answer:
that's is a theory
Explanation:
hope it may help you
Soot is formed as a candle burns
a
Chemical Change
b
Physical Change
Answer:
Chemical change
Explanation:
Because a new substance is formed.
Convert 6.5 cm3 to m3
the Answer is
6.5e-6 m^3
[6.5e-6 = 6.5 x 10-6 = 0.0000065]
Answer:
0.0000065 m³
Explanation:
To convert a cubic centimeter measurement to a cubic meter measurement, divide the volume by the conversion ratio.
Since one cubic meter is equal to 1,000,000 cubic centimeters, you can use this simple formula to convert:
cubic meters = cubic centimeters ÷ 1,000,000
m³ = 6.5 ÷ 1,000,000
m³ = 0.0000065
(b) Liquids and gases flow because…?
The molecules of gases and liquids are present far apart from each other. In other words, they have more gaps or intermolecular spaces. Due to the large intermolecular forces, the intermolecular attractions are very less and thus liquids and gases can flow.
Balance the following chemical equation and explain how u got it
a. Fe + O2 →Fe2O3
b. FeBr3 + H2SO4 → Fe2(SO4)3 + HBr
c. C4H6O3 + H2O → C2H4O2
Explanation:
just trying...hope that helps
on what bases are the elements of periodic table classified?
The elements can also be classified into the main-group elements (or representative elements) in the columns labeled 1, 2, and 13–18; the transition metals in the columns labeled 3–12; and inner transition metals in the two rows at the bottom of the table (the top-row elements are called lanthanides and the bottom-row ...
Hello,
What are Elements?Elements are a group of the Periodic Table that shares common valence electron structures. They are arranged in order of increasing Atomic Number.
Now back to the question:-In modern periodic table they are classified into three parts- metals, non-metals and metalloids.
In detail:-
• Metals- Metals are those elements which donate electrons. Ex- Na, K, Rb, Mg, Ca, etc.
• Non-metals- Non-metals are those elements which accept electrons. Ex- N, O, F, Cl, etc .
• Metalloids- Metalloids are those elements which show property of both metals and non-metals. Ex- B, Si, Ge, etc.
Hope it helps...
(by Benjemin)
Describe the color change that would be observed in water in left hand beaker
Answer:
is there supposed to be a photo with this?
Explanation:
I need help on this, It’s due today. Please, anybody
Answer:
1 = 252g, 2 = 2mL, 3 = 1.5mL, 4 = 3g, 5 = 225g, 6 = 0.92g/mL, 7 = 0.75g/mL, 8 = 0.71g/mL, 9 = 1.9mL, 10= 1.11mL, 11 = 76.9g
Explanation:
This problem is testing how well you can move around the equation D = m/v where D = Density (g/mL), m= mass of sample (g), v = volume of sample (mL).
Could someone plz help me? :(
Answer:
eu sou do brasil :D gostaria de saber como é ai nos estados unidos :D
Explanation:
Answer:
Explanation:
I think that C is the best limitation you could pick. I doubt you could be on the beach at 4 am. So the gulls that visit the beach would be unknown to you at night. That's half the day you could not account for.
what dose gravity measure ?
Answer:
the acceleration that it gives to freely falling objects.
Explanation:
i took quiz
Helppppp….. is this right?
Answer:
there's no attachment
Explanation:
.
Answer:
6 mL = Smallest
600 cL = Middlest
60L = Greater
You want to test the effect of soil acidity on plant growth. Which of the
following is an example of a controlled experiment to test this?
A. The plant type, amount of light, and amount of water are kept
constant while soil acidity is varied for plants in a greenhouse.
B. The soil acidity of plants in a garden that get light and water from
their surroundings is increased after the plants grow to a height of
100 cm.
C. The plant type, soil acidity, amount of light, and amount of water
are all varied and studied in a laboratory.
D. Soil acidity and height of plants growing in a 10 m2 yard are
measured twice in July and twice in August.
Answer:
I believe the answer to your question would be A. this is because it is controlled with a good habitat and also has good variants that are needed in a good plants growth.
Explanation:
What is astronomy? Why is the study of astronomy important to humans?
Answer and Explanation:: Astronomy is the study space and what it contains. Astronomy should be studied by mankind because our survival is directly linked to the cosmos. The Earth is heated by its nearest star, the Sun, and its ocean tides are directly connected to its only satellite, the Moon.
Answer:
Astronomy is the study of stars and planets. It is important to humans because it helps us know if there is a supernova close to earth and more imformation about stars and planets that we need to know.
what is true about chemicals?
A. Chemicals are rarely found on earth
B. Chemicals are never dangerous
C. Chemicals are in many substances in a home
D. Things containing chemicals always cost a lot of money
hi <3
i believe the correct option would be C
hope this helps :)
In a titration, when the number of moles of hydrogen ions equals the number of moles of hydroxide ions, what is said to have happened?
The equivalence point has been reached.
The point of neutralization has been reached.
The end point has been reached.
What is the equation to calculate the volume of a cylinder?
O V = (77/4)*72 +h
O V=1* w* h
O V = (4/3)*r
O V = m*d2
Answer:
the equation for cylinders is V = (pi)r2h
none of these are even close but i can do a little more research
sorry if this one wasnt as much help
A block of aluminium occupies a volume of 15.ml and weighs 40.5 g. What is its density? 2700kg /m3
Answer: d = 2.70 g/mL
Explanation: Considering we know that it weights 40.5 brains and the volume of such amount is 15 ml we can calculate such in which it comes to be 2.7 grams per mL