What is the difference between melting and burning a substance? Is mass conserved in either process?
Answer:
Explanation:
First Question:
Melting is a physical process that involves the phase transition of a substance from its solid to its liquid state. Burning, on the other hand, is a chemical process that involves a substance being broken down and changed into different substances. It's still the same substance, though: water.
Second Question:
Mass is therefore never conserved because a little of it turns into energy (or a little energy turns into mass) in every reaction. But mass+energy is always conserved. Energy cannot be created out of anything.
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Answer:
translation to English please
what does feldspar mean?
Answer:
an abundant rock-forming mineral typically occurring as colorless or pale-colored crystals and consisting of aluminosilicates of potassium, sodium, and calcium.
Explanation:
Answer:
Feldspars are a group of rock-forming aluminium tectosilicate minerals, containing sodium, calcium, potassium or berium
If a barometer were built using water (d=1.0 g/cm3) instead of mercury (d=13.6 g/cm3), would the column of water be higher than, lower than, or the same as the column of mercury at 1.00 atm? If the level is different, by what factor? Explain.
Mercury is a compound denser than water and when this happen, it stays lower.
So, in this case, water stays higher than mercury because its density is low.
The level is different by a factor of 13.6 times taller.
a guy walks into a bar and sees a non-linear person. he says hey wt y=mx+b is this? he threw a sploddy gun grenade in the place. how many non-linear people did he hurt?
Question 10
What is this structure name?
CH3 – CH2 - CH
CH – CH – CH2 - CH2
CH; CH – CH, -CH,
СН
CH3
cosh(-cosh(-CH
Simplify the expression using the symmetry of hyperbolic functions
cosh(cosh(CH))
Simplify the expression using the symmetry of hyperbolic functions
the answer is cosh(cosh(CH))
A gas has a volume of 1140 ml at 37 ºC and 620 mm Hg pressure. Calculate its volume at STP.
1.900
2.800
3.819
4.1000
Answer:
3. 0.819L (819 mL)
Explanation: Before we go about solving this, we need to do some conversions prior to using the gas law, the gas law is as follows...
P(atm)*V(L)=n(mol)*r(constant)*T(in kelvin)
So here are all the conversions you need.
620 mm Hg -> 0.816 atm
1140 mL -> 1.14 L
37 C -> 310.15 K
After plugging in our new converted values, we will proceed to solve the number of moles of the gas present, our n value, so our equation will look like this...(Note: Constant r in this case is 0.08206 L*atm/K*mol)
(0.816 atm)(1.14 L) = n(0.08206)(310.15)
Solving for n we get 0.03653 moles.
Now our second part is to figure out the volume AT STP (standard temperature/pressure). In the STP conditions, your temperature defaults to 0 C (273.15 K) and 1 atm. Now there is an easier way to do this, but I'll also show the more comprehensive way. Here is the easier method...
Since 1 mole of every gas occupies 22.4 L at STP, we can simply multiply this by our number of moles. So (22.4L)(0.3653 mol) to give us 0.818272.
However, a more accurate answer can be given like this...
Plugging n back into the same equation and this time resetting pressure to 1 atm and temperature to 273.15 K and conserving our number of moles we get...
(1 atm)(v) = (0.03653 mol)(0.08206)(273.15 K)
v = (0.03653)(0.08206)(273.15)
v = 0.8188 L = 0.819 L or 819 mL
A chemist makes up a solution by dissolving 42.0 g of Mg(NO3)2 in enough water to produce a final solution volume of 213 mL. To calculate the molarity of the solution, what additional information is needed
Answer:
the molar mass of Mg(NO3)2
the mass of the water added the density of the Mg(NO3)2
the volume of water used
Calculate the number of moles of Mg(NO3)2 used to make up this solution. 42.0 g of Mg(NO3)2 is equivalent to___ mol Mg(NO3)2.
Now calculate the molarity of the solution, giving your answer to the correct number of significant digits.
Molarity of Mg(NO3)2 = ___M
name 2 elements that are liquid at room temperature and describe their colour
Answer:
Bromine
Mercury
Bromine (symbol Br and atomic number 35) is a reddish-brown liquid, with a melting point of 265.9 K. Mercury (symbol Hg and atomic number 80) is a toxic shiny silvery metal, with a melting point of 234.32 K.
what do we call the cammell their
Answer:
You have to write the full question
How does the structure of compounds determines the properties of the compounds?
All of these properties are due to the chemical structure of the compound. The chemical structure includes the bonding angle, the type of bonds, the size of the molecule, and the interactions between molecules. Slight changes in the chemical structure can drastically affect the properties of the compound.
What is the chemical composition of shale?
Answer:
30.8 percent quartz, 4.5 percent feldspar, 3.6 percent carbonate, <0.5 percent iron oxides, 60.9 percent clay minerals, 1 percent organic material, and 2 percent other materials.
What would be the atomic number of this atom?
Answer:
1 would be the answer
protons = atomic # I think
Answer:
hydrogen
Explanation:
hydrogen has the atomic number of 1 which means that hydrogen has one proton and is neutral so it has one electron as well.
20 points! Please Help!!
Based on what you have read what is the opportunity cost of the glass-making company's decision?
a higher quaity tem
a greater proft
a loss of equipment
a longer production time
Answer:
a greater profit......
Help with this pretty please!
Answer:
10
Explanation:
Basically same as last question but the number is before the compound :)
Suppose you are performing a titration. At the beginning of the titration, you read the titrant volume as 2.51 mL. After running the titration and reaching the endpoint, you read the titrant volume as 29.95 mL. What volume, in mL, of titrant was required for the titration
The volume of titrant required for the titration would be 27.44 mL
From the illustration, the initial titrant volume was 2.51 mL. This figure represents the initial reading on the burette.
In the same vein, the final volume of the titrant was 29.95 mL. This figure represents the final reading on the burette.
In order to get the volume of titrant used:
Volume of titrant used = final volume - initial volume
= 29.95 - 2.51
= 27.44 mL
More on the volume of titrant used in titrations can be found here: https://brainly.com/question/4250180
what are aliphatic alcohols and what differentes it from other alcohols
Answer: Lipids are one of the important nutrients needed by the body to supply energy and essential fatty acids required by the organism. Solid alcohols are a class of steroids, which are steroids containing hydroxyl groups. Lipids is a general term for oils, fats and lipids. 2, the characteristics are different: fat consists of c, h, o three elements. Fats are triacylglycerides made up of glycerol and fatty acids.
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True or false?
Increasing the temperature can help slow down chemical reactions by "burning away" unnecessary molecules
Calculate the amount of energy That an obsect Can absorb from Yellow light Whose wave length is 589 nm.
Explanation:
E = hf
c= f × lamda
f= c/ lamda
c= speed of light
f= frequency
lamda = wavelength
E = h c/ lamda
E = 6.626 × 10^-34 Js × 3 × 10^8 ms-1 / 589 × 10^-9 m
= 3.37 × 10^15 J
What’s the answer to this
Answer: 5
Explanation:
please brainliest me
I believe it is 3
Answer:
Explanation:
HELPP PLISS :(
Achemist analyzes two samples. One sample contains 14 g of element X and 6.0 g of element Y. The second sample contains 28 g of element X and 6.0 g of element Y. Does it appear that the two samples are the same substance? Explain the reasons for your answer.
A chemist analyzes two samples. One sample contains 14 g of element X and 6.0 g of element
A mixture of two or more metals is called: A) Mixture B) Compound C) solution D) alloy
Answer:
C
Explanation:
Mixture of 2 or more metals is a compound
example is water which is made up of hydrogen and oxygen.
A mixture of two gases with a total pressure of 2.78 atm contains 0.70 atm of Gas A. What is the partial pressure of Gas B in atm
Answer:
2.08 atm
Explanation:
Here we use Dalton's Law of Partial Pressures: Pa+Pb=Ptotal. 0.70 atm + Pb = 2.78 atm. To find the missing pressure of gas b we subtract .7 from the 2.78
14. What type of materials are spun together to make yarns?
Answer:
cotton
Explanation:
which is typically spun into fine yarn for mechanical weaving or knitting into cloth.
Hey :3 please help with this. Will mark brainlist if you’re right
Answer: 4
Explanation:
Which ion with a
+2
charge has the electron configuration
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6?
Answer:
atomic # 38 or strontium (Sr)
Explanation:
Which ion with a
+2charge has the electron configuration
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6?
ADD THE ELECTRONS AND ADD 2 MORE FOR THE +2 CHARGE
so
2 +2 +6 +2 +6 +2 + 10 + 6 +2
so if it is now neutral (you added 2 e's to ofsetr the +2 charge) it has 38
protons, so it is atomic # 38 or strontium (Sr)
help! giving brainliest.
Answer:
A
Explanation:
will group 2 elements gain electrons to bond with non-metals in group 16 in a 2:1 ratio
375cm³ of a gas has a pressure of 770 mm Hg, find it Volume if the pressure is reduced to 750 mm Hg
Answer:
Explanation:
Givens
v1 = 375 cm^3
P1 = 770 mm Hg
V2 = ?
P2 = 750 mm Hg
Formula
V1 P1 = V2 P2
Solution
375 * 770 = V2 * 750 Combine the left
288750 = V2 * 750 Divide both sides by 750
288750/750 = V2
V2 = 385
how to draw ethyl structural formula?
Answer:
c2H5
Explanation:
H. H
|. |
C-C- H
|. |
H. H