Which of the following is a property of elements?
O
Elements have at least two different types of atoms.
Elements have their own individual characteristic properties.
Elements are can be separated from one another.
Elements have the ability to change into a different element.
A photon of visible light can be emitted when
Select one:
O a. an excited electron jumps down to ground state
O b. a ground state electron absorbs energy
O c. a ground state electron jumps to a higher energy level
Answer:
a ground state electron jumps to a higher energy level
What is the pH of a 0.30 M solution of Ca(OH)2?
Explanation:
30 to the second power
Which on is right O& Mg?
OMG
MgO
Mg2O2
Mg+2O-2
Answer:
MgO
is the correct answer
hope it helps
pls help and show work!!!
Answer:
44.9g
Explanation:
You have to convert grams of CH4 to moles, use the mole-to-mole ratio of CH4 to water, and convert back to grams.
(20.0g CH4)(1 mol CH4/16.04g)(2 mol H2O/1 mol CH4)(18.01 g H2O/ 1 mol) = 44.9127 g
Hope this helps!
2-ciclopropilpropano
Answer:
cool
Explanation:
6. Find the number of molecules in 33.6 L of co, at STP? What is the name
of this compound?
!!!!!!PLEASE HELP!!!!!!!!!!
explain in 3 complete sentences
Answer:Air in high pressure systems moves in an anticlockwise direction (in the southern hemisphere), while air in low pressure systems moves in a clockwise direction due to the rotation of the Earth. At the surface of the Earth air flows from high pressure systems into low pressure systems.
Explanation:
Warm air rises, creating a low pressure zone; cool air sinks, creating a high pressure zone. Air that moves horizontally between high and low pressure zones makes wind.Smaller pressure systems create localized winds that affect the weather and climate of a local area.
4. What is the volume of 6.5 moles of Helium at STP?
|
Answer:
Volume of 6.5 moles of Helium at STP is 145.6954 L
Explanation:
As we know
[tex]pV = nRT[/tex]
At STP, temperature is 273.15 K and pressure is 1 atm
n is the number of moles which is equal to 6.5
R is the gas constant = 0.08206 L atm/K mol
Substituting the given values in above equation, we get -
[tex]1 * V = 6.5 * 0.08206 * 273.15\\V = 145.6954[/tex]Liters
Volume of 6.5 moles of Helium at STP is 145.6954 L
Now that you have exercised, walked your
jackalope, made cookies, and had juice, you
decide on a nap. Your body uses melatonin to
tell your brain and body that it's ready to sleep
or nap. Melatonin has the chemical formula
C13H16N2O2. The amount in your body at any
time is very small - less than 10 milligrams
(0.01 g)! Convert the melatonin to moles so
you can rest
Answer: The moles of melatonin are 0.000043
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to its molecular mass and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
To calculate the moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}[/tex]
Given mass of melatonin = 0.01 g
Molar mass of melatonin [tex](C_{13}H_{16}N_2O_2)[/tex] = 232.28 g/mol
[tex]\text{Number of moles of melatonin}=\frac{0.01 g}{232.28g/mol}=0.000043mol[/tex]
Thus the moles of melatonin in 0.01 g are 0.000043
Calculate the molar mass of HCI.
5 Which two elements are combined in magnesium oxide?
Answer:
magnesium and oxygen
Explanation:
Texas hill country is largely composed of soft limestone rock. When exposed to carbonic acid in rainwater, limestone can deteriorate and weaken. What affect does this process have on the landforms of Texas hill country?
Answer:
The answer is "It leads to the formation of underground caves"
Explanation:
Texas Hill Land is popular for its rolling hills, good wine, and authentic food. Its Texas Hill Property appeal is no mystery, recognized as being one of the top vacation destinations in the World. Texas Hill Structure is primarily mostly of weak calcareous stone. Calcium may worsen or degrade if exposed to carbon dioxide in rainwater. This practice affects the land of the Texas smoky Mountains leading to the formation of underwater groves.
Which substances are compounds? Please help
Answer:
1 and 3
Explanation:
oh this one lol,, hope it helps
Answer:
1 and 3
Explanation:
hope this helps :)
Please please help me!! It needs to be turned in in a few minutes!
Answer:
D. Thermal
Thermal is another energy the match gives off
What is the normality of a 2.0 M NaOH solution?
Answer:
Normality= molarityX total POSITIVE oxidation number of solute Solvent=substance present in the greatest amount Solute= all other substances in the solution +1 (1 na+) is the total POSITIVE oxidation number of NaOH 2.0X1= 2.0 N=2.0
Explanation:
I had the same question on one of my assignments earlier
2 H2 (g) + O2 (g) --> 2 H2O (l)
How many moles of hydrogen gas do you need to make 2 moles of liquid water?
Answer:
2H2(g]+O2(g]→2H2O(l]]. Notice that the reaction requires 2 moles of hydrogen gas and 1
Explanation:
Which statement is true about the particles of a liquid when the liquid changes into a solid?
They move closer to each other.
Their kinetic energy increases.
They stop vibrating.
The attractive force between them decreases.
Answer:
they move closer to each other
Answer:
They move closer to each other
Explanation:
Got it right on the test
Hope this helps :)
A pool float was filled with air to capacity in the middle of a hot day. The next morning the pool float looked different yet no gas escaped or entered the float. Describe what you think the float looked like in the morning and why it occurred.
Answer:
The pool float looked would have looked deflated the next morning.
Explanation:
When temperature decreases the volume decreases
Answer:
The pool float most likely looked a little deflated or pushed in
Explanation:
The pool float most likely looked a little deflated or pushed in. This is because during the night temperatures most likely dropped. These cold temperatures during the night would have caused the air molecules inside the pool float to come closer together which would cause there to be more excess space inside the pool float. Therefore, allowing it to collapse into itself. This would be far worse if the float was filled with helium or another gas other than O2.
A box slides with an initial speed of 4.0 towards a spring on a frictionless horizontal surface. When the box
S
N
hits a spring with spring constant k = 150 the spring compresses by 0.30 m.
m
m
M
What is the mass of the box?
Answer: .84kg
Explanation:
Khan academy
A box slides with an initial speed of 4.0 kg m/s towards a spring on a frictionless horizontal surface. When the box hits a spring with spring constant k = 150 N/m, the spring compresses by 0.30 m.
What is the mass of the box?
Answer: 0.54 kg
How many moles are in 3.4*10²⁶ molecules of H2O?
Answer:
564.5027395 moles
Explanation.
a mole is 6.023×1023
(3.4×10^26)÷(6.023×10^23)= 564.5027395
An electric car has a mass of 2,000 kg. the engine is producing a force of 3,500 N to move the vehicle forward,but it must overcome air friction equal to 500 N
What is the acceleration of the electric car m/s2?
record your answer and fill in below
Answer:
1.5 m/s²
Explanation:
From the diagram,
F-F' = ma............... Equation 1
Where F = Forward force of the vehicle, F' = Frictional force, m = mass of the electric car, a = acceleration of the car.
make a the subject of the equation
a = (F-F')/m........... Equation2
Given: F = 3500 N, F' = 500 N, m = 2000 kg
Substitute into equation 2
a = (3500-500)/2000
a = 3000/2000
a = 1.5 m/s²
Horticulture 100 POINTS Hurry
Which of the following is an example of an indirect expense?
A. corn oil
B. animal fodder
C. export commodity
D. snack foods
Answer:
B!
Explanation:
Answer:
i know im late but i just really want the points. the answer is b.
Explanation:
4Fe+3O2 →2Fe2O3
80.0 grams of iron are reacted with 50.0 grams of oxygen gas. Which of these reactants are the limiting reactant, and how many grams of iron (III) oxide would be produced?
Answer:
FFe
2
O
3
(
s
)
+
3
CO
(
g
)
→
2
Fe
(
s
)
+
3
CO
2
(
g
Explanation:
How many grams of NaOH are produced from 2.1g of Na2O?
Na2O + H20 --> 2NaOH
Answer:
2.72g
Explanation:
The balanced equation of this reaction is given as follows:
Na2O + H20 --> 2NaOH
Based on this balanced equation, 1 mole of Na2O will produce 2 moles of NaOH.
First, we need to convert mass of Na2O into moles by using the formula;
mole = mass/molar mass
Molar mass of Na2O = 23(2) + 16
= 46 + 16
= 62g/mol
mole = 2.1g/62g/mol
mole of Na2O = 0.034mol
Hence, if 1 mole of Na2O will produce 2 moles of NaOH.
Then, 0.034mol of Na2O will produce (0.034 × 2) = 0.068mol of NaOH.
To convert mole of NaOH to mass, we use;
mole = mass/molar mass
Molar mass of NaOH = 23 + 16 + 1 = 40g/mol
0.068 = mass/40
mass of NaOH produced = 2.72g.
How many moles are in 564 grams of copper
Answer:The answer is 63.546.
Explanation: The answer is 63.546. We assume you are converting between grams Copper and mole. You can view more details on each measurement unit: molecular weight of Copper or mol. The molecular formula for Copper is Cu. The SI base unit for amount of substance is the mole. 1 grams Copper is equal to 0.015736631731344 mole
Answer:
5.64 of copper
Explanation:
Given: 564 grams of copper
To find: in copper
Solution: If 1 grams Copper = 0.01 mole,
Then, 564 grams = multiply 564 and 0.01 mole
564 × 0.01 = 5.64
Therefore, there are 5.64 of copper in 564 grams
The shoes are green, a size 8, have white laces, made out of cotton, and have a rubber sole. The description given is a list of ___________ properities of the shoes. Question 33 options:
chemical
mechanical
physical
structural
Answer:
Physical i think, because it says, "The shoes are green, made of cotton, and rubber sole" everything in the passage described a physical property
Explanation:
tell me if im wrong, good luck
Answer:
physical
Explanation:
its listing a size 8, which eliminates chemical and mechanical. Also it lists their green, which eliminates structural, leaving physical left
What type of ionic compound is CO3?
Answer:
Carbon Trioxide
Explanation:
Its a Carbonite Ion which is also known as a polyatomic ion
When hydrogen peroxide (H2O2) is used in rocket fuel, it produces water and oxygen (O2): Can someone help with parts B and C?
Answer:
Explanation: A foam forms when bubbles of a gas are trapped in a liquid or solid. In this case oxygen is generated when hydrogen peroxide breaks down into oxygen and water on contact with catalase, an enzyme found in liver. Enzymes are special protein molecules that speed up chemical reactions.
How are Earth;s Days, Years, and Season’s related to the way Earth moves in Space?