Answer:
Physical change
Explanation:
No new substances were produced so it is physical change.
Answer:
Physical Change
Explanation:
Since only the temperature is changing not the structure of tea its a physical change. Good luck ;)
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
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
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
Which two subatomic particles have the same mass but do not have the same charge?
A. None of these
B. Neutrons and quarks
C. Electrons and neutrons
D. Protons and neutrons
Answer:
d
Explanation:
b/ce The strong force effects produce a mass that is essentially independent of the kinds of quarks involved, so this mass contribution will be the same for the proton and neutron.
(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.
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.
If an object has a mass of 43.23 g and a volume of 32.1 mL, what is its density? Show your work!
Answer: 1.34 g/ml
Explanation: Density is an objectives mass divided by it's volume:
(43.23 g)/(32.1 ml) =1.34 g/ml
someone helpppp ill brainlist!! this is so confusing.
Answer:
Well in short, if u want more explanation u can ask
1. Only one side benefits
2. Plants needs sunlight for photosynthesis, so if a large plant is blocking all that sunlight, that small plants won't have sufficient sunlight
1) The predator or parasite both derive nutrients from the other organism.
Usually predators quickly kill the prey while parasites slowly weaken or kill their host
2) The plant blocks sunlight from reaching smaller plants. This is an issue because
without the sun, plants can't get the food they need to grow, reproduce and survive. This hinders their ability to photosynthesize
3) fox and rabbit
flower and bee
whales and barnacles
dog and tick
Do experiments always turn out as
expected? Why or why not?
Answer:
no
Explanation:
When doing experiments, it's to find out how what you're doing will end up in the results. Even when expecting something, it may not end up that way. Trial and Error you could say
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:
Which of these things are NOT listed in the periodic table?
Element Name or Symbol
Atomic Weight
Atomic Number
Atomic Orbital Radius
what dose gravity measure ?
Answer:
the acceleration that it gives to freely falling objects.
Explanation:
i took quiz
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
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
9
23 What is a use of sulfuric acid?
A
as a bleach
B.
as a food preservative
in the manufacture of detergents
D.
in the manufacture of
vanadium(V) oxide, V205
Answer:
B. as a food preservative in the manufacture of detergents
.........
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.
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
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.
Define density, and list two reasons it is important in science
Answer:
The density is the mass per unit volume of a substance.
Density is important when working out if something will float in water, and it can also be useful for calculating the mass of a specific volume of a substance.
Explanation:
La temperatura más baja registrada en EEUU fue de - 70 °F (en Roger Pass montana). Exprese esta temperatura en °C
(Porfavor ayudenme)
Answer:
[tex]thank \: yo[/tex]
Acetylene, C2H2, burns according to the following reaction: C2H2 5O2 --> 4CO2 2H2O. Suppose 1.20 g of C2H2 is mixed with 3.50 g of O2 in a closed, steel container, and the mixture is ignited. What substances will be found in the mixture left when the burning is complete
C2H2 will be left when the burning is complete.
The equation of the reaction is; 2C2H2 + 5O2 --> 4CO2 + 2H2O
The number of moles of C2H2 reacting is = 1.20 g/26 g/mol = 0.046 moles
The number of moles of O2 is = 3.50 g/32 g/mol = 0.109 moles
Since;
2 mole of C2H2 reacts with 5 moles of O2
x moles of C2H2 reacts with 0.109 moles of O2
x = 2 mole × 0.109 moles/5 moles
x = 0.044 moles of C2H2.
It then follows that C2H2 is the reactant in excess so C2H2 will be left when the burning is complete.
Learn more: https://brainly.com/question/9743981?
Explain why nitrogen is a gas at room temperature.
Answer in terms of nitrogen's structure.
Nitrogen exists as a diatomic molecule, N2 (subscript 2). It exists as a gas at room temperature because of the type of interactions with other identical molecules: weak intermolecular forces are present between the molecules, specifically temporary dipole-dipole interactions.
These interactions are the second weakest type of intermolecular force (Van Der Waals and Hydrogen Bonds are the other two with Hydrogen Bonds being stronger).
Now the reason why Nitrogen exists as gas is that these weak intermolecular forces can be overcome with little energy. Therefore, at room temperature, Nitrogen exists as a gas.
What is nitrogen gas at room temperature?Nitrogen has a low melting and boiling point and is a gas at room temperature. The Earth's atmosphere is made up of 78% nitrogen. The next most common gas is oxygen, at 21%. Nitrogen isn't very reactive, but it can react with oxygen at high temperatures, such as in-car engines.
What is the nitrogen structure?Nitrogen forms an extensive series of nitrides with carbon, including those with chain-, graphitic-, and fullerene-like structures.
Learn more about What is nitrogen gas at room temperature? here: https://brainly.com/question/14747312
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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
What does a virus inject into a cell?
Answer:
The virus's genome is uncoated from the protein and injected into the host cell.
Explanation:
Soot is formed as a candle burns
a
Chemical Change
b
Physical Change
Answer:
Chemical change
Explanation:
Because a new substance is formed.
A photon of 498nm was emmited from a silicon atom. Calculate the energy of all the atomic levels of silicon and show that The atomic levels are quantized
Answer:
3.99 × 10 ^-28
Explanation:
In the equation of E = hc/λ, the h = 6.626 × 10^−34 J and c = 3 × 10^8 m/s
E = 6.626 × 10^−34 × 3 × 10^8 divided by 498
E = 3.99 × 10 ^-28
An Erlenmeyer flask holds
19.0 g of a liquid that takes
up a volume of 25.0 mL.
What is the density of the
liquid?
Taking into account the definition of density, the density of the liquid is 0.76 [tex]\frac{g}{mL}[/tex].
First of all, density is defined as the property that matter, whether solid, liquid or gas, has to compress into a given space.
In other words, density is a quantity that allows us to measure the amount of mass in a certain volume of a substance.
Then, the expression for the calculation of density is the quotient between the mass of a body and the volume it occupies:
[tex]density=\frac{mass}{volume}[/tex]
From this expression it can be deduced that density is inversely proportional to volume: the smaller the volume occupied by a given mass, the higher the density.
In this case, you know:
mass= 19 gvolume =25 mLSo, replacing in the definition of density:
[tex]density= \frac{19 g}{25 mL}[/tex]
Solving:
[tex]density= 0.76 \frac{g}{mL}[/tex]
Finally, the density of the liquid is 0.76 [tex]\frac{g}{mL}[/tex].
Learn more about density:
brainly.com/question/952755?referrer=searchResults brainly.com/question/1462554?referrer=searchResultswhat 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 :)
Explain the four basic types of chemical reactions. Be sure to include a sample equation for each type. Describe how rate relationships and activation energy are important in chemical reactions.
Answer:
Synthesis reaction is 2 or more chemical combing to form complex product (A+B→AB)
Decomposition occurs when one reactant breaks down into 2 or more products (H2CO3→H2O+CO2)
Single replacement is a reaction when one element is substituted for another element compound. (A+BC→ AC+B)
Double replacement occur when parts of 2 ionic compounds are exchanged making two new compounds .(A+B - + C + D- → A+D- +C )
The activation energy of the particular reaction will determines the rate at which it will go. The higher the activation energy gets, the slower the chemical reaction will become.
Explanation:
A decrease in temperature reduces the volume of gas
a
Chemical Change
b
Physical Change
Answer:
Chemical change.
Hope this helps you.