Answer:
A
Explanation:
The number of protons and neutrons of an element is the same. the electrons are the only thing that can differ. The atomic number equal the protons and neutrons.
HELP plis !
Find the molar masses of the following compounds: SHOW ALL WORK!!!
1) LiI. Li. 7 + I 127
134g/mol
2) PbCO4
Pb =. 1 x 207 =207
C = 1 X 12 = 12
O = 4 x 16 = 64
283 g/mol
3) Mg(OH)2
Mg= 1x 12 = 12
O= 2 x16 =32
H= 2x1= 2
46 g/mol
4) K3PO4
5) (NH4)3PO4
6) C12H22O11
7) Fe2(SO4)3
8) Na3P
9) AgF
10) NH4C2H3O2
Which of the following is a group of tissues that work together to carry out a
function?
A. Body system
B. Organs
C. Tissues
D. Organism
What is the molar mass of AlCl3
Answer:
133.34 g/moles
Explanation:
but to make life easy it could be 133.4 g/ moles as well
3.org bookmarks
B Classes
Next.
Reaction Rates and Chemical Equilibrium: Mastery Test
Select the correct answer from each drop-down menu.
What effect does a decrease in temperature have on the overall rate of a chemical reaction?
The reaction rate will
A decrease in temperature decreases(blank)
The reaction rate will (blank)
Answer:
A decrease in temperature decreases the number of collisions between molecules . The reaction rate will decrease
Explanation:
Which action would not help a person stay safe during a tornado? O A. Moving away from outside walls B. Going into a storm shelter or basement O C. Driving to get supplies OD. Staying away from windows
Answer:
Driving to get supplies
Explanation:
Which of the following galaxies do not have a regular structure?
A. Elliptical and barred spiral galaxies
B. Irregular and elliptical galaxies
C. Spiral galaxies
D. Irregular galaxies
Answer: D
Explanation: Irregular galaxies
Answer:
Your answer is D
Explanation:
Irregular galaxies do not have a regular structure.
what happened to the sound as vibration of an object increase in strength
Answer:
A.The sound becomes louder.
And
C.The sound waves get further.
Explanation:
Louder the sound it will travel long.
Today, there are ____ GMO crops currently produced in the US.
A. 120
B. 10
C. 55
D. 1000
Answer: I think that is 55
Explanation: I hope I help
a 55g block of metal has a specific heat of 0.45 J/g°C. What will be the temperature change of this metal if 450 J of heat energy are added
Answer:
18.18C
Explanation: Write whats below to show your work :D
m=55
C=0.45
Q=450zj
ch.temp=?
Q=mct
450 = (55)(.45)T
450 = 24.75
/24.75 = /24.75 (cancels out)
18.18 is the answer
Hope this helps! did it with my teacher.
A gas under a pressure of 9.86 kPa and at a temperature of 75°C occupies a 500.0L container. How many moles of gas are in the container?
Answer:
1.7 mol
Explanation:
This is an ideal gas problem. So many units! That's the tip-off usually.
PV=nRT
First convert kPA to atm 1 atm=101.3 kPA so 9.86/101.3 = .097311 atm
(.097311 atm x 500L) = n · 0821 L·atm/mol·K · 348K
Do your multiplication then divide to get n alone and you should get 1.7 mol
What is the scaling factor if the molar mass of
this compound, having an empirical formula of
ch2o, is 150 g/mol?
Answer:
The scaling factor is 5.
Explanation:
Hello there!
In this case, since the scaling factor is defined as the ratio of the molar mass of the molecular formula (complete) to the empirical formula (simplified), it is possible to compute it for the empirical formula of CH2O whose molar mass is 30 g/mol (12+2+16) as shown below:
[tex]sf=150/30=5[/tex]
Therefore, we can also infer that the molecular formula would be:
[tex]C_5H_1_0O_5[/tex]
Best regards!
Given a volume of 47.8 mL of gas at STP, _______________ moles of O2 exist
5. What physical property of foam makes it a good choice to
use in life vests?
A. Foam has a relative density less than water.
B. Foam is a good thermal insulator.
C Foam is non-magnetic.
D. Foam is soluble in water.
Which of the following molecules has a bent shape?
O A. CO2
O B. H20
O C. BeCl2
O D. NH3
See if you can complete the following table using only what is on this page. Hint: Two of the entries are for the same element.
Element
Symbol
Nuclear
Symbol
Atomic Mass
Protons Neutrons Electrons
Number Number
83 Cu
29
Ga
67
31
29
36
Answer:
See attached picture.
Explanation:
Hello there!
In this case, according to the given information, it is possible to complete the table by knowing that the atomic number is the same to the number of protons equals those of electrons and that the neutrons are calculated by subtracting the atomic mass and the protons; thus, we are able to obtain the result as shown on the attached picture.
Best regards!
What is a renewable resource on Earth?
minerals
coal
wind
petroleum
Answer:
Wind
Explanation:
Wind turbines make energy by the movement of the natural force on earth called 'wind' and renewable resources are resources that can be made from natural and environment-safe objects or things (e.g. Water, Geothermal Heat, The Sun, and Wind)
how many moles are there in 2.20 x 10^23 molecules of Na2SO4
Answer:
Explanation:
450 grams of Na2SO4? 450 Na soullnol Na2SO4 16.02x1023 molec, Na₂SO4 = 119x1024. | 142.05g Na25041 Imol Naz
WILL AWARD BRAINLIEST! I NEED HELP PLEASE! Match the states of matter for each of the five lines below.
Answer:
see explanations
Explanation:
The graphic is the heating curve for water. Note that it is divided into 5 distinct heat flow segments. The segments with changing slopes are single phase segments with changes in temperature values. From left to right segment A is solid ice being warmed to it's melting point. Segment B is the melting segment in which 2 phases are in contact (solid + liquid). Note that addition of heat does not change the temperature. Segment C is warming of the liquid (single phase) up to its boiling point. At the boiling point the liquid begins to pass into the gas phase and again 2 phases are in contact; i.e., liquid & gas. Note again when two phases are in contact no temperature change occurs. Finally, segment E is the heating of the pure, single phase gas.
In summary ...
Segment A => heating single phase (solid) ice up to melting pt.
Segment B => melting of ice => 2 phases in contact (s & l) ΔT = ∅.
Segment C => heating single phase (liquid) water up to boiling pt.
Segment D => boiling of liquid => 2 phases in contact (l & g). ΔT = ∅.
Segment E => heating single phase (steam) up to desired temperature.
For what it's worth, the equation for the segments that show increasing temperature values is q = mcΔT (m= mass, c = specific heat & ΔT temp change.
The segments with zero slopes (horizontal lines) are defined by equations q = m·ΔHₓ where m = mass & ΔHₓ = heat of fusion (a constant = 335 j/g). The same is true for the line at 100°C where q = m·ΔH(v) where m = mass & ΔH(v) is the heat of vaporization (a constant = 2259 j/g.
Calculations involve calculating the amount heat transfer for each segment individually and then adding the heat values to obtain the total heat transfer.
If you need more instruction on this topic, kick back a note and I'll try to help clarify. Good Luck, Doc :-)
Answer:
Picture attached has answers
Explanation:
What is the molarity of a 250ml KCl solution made by diluting 175mL of a 3.00 M solution?
Answer:
2.1 M
Explanation:
The dilution equation is [tex]M_{s} V_{s} = M_{d} V_{d}[/tex].
[tex]M_{s}[/tex] = the molarity of the sock solution
[tex]V_{s}[/tex] = the volume of the sock solution
[tex]M_{d}[/tex] = the molarity of the diluted solution
[tex]V_{d}[/tex] = the volume of the diluted solution
The stock solution would be what is doing the diluting, so "175 mL of a 3.00 M solution". So [tex]M_{s}[/tex] = 3.00 M. Then: Converting 175 mL to liters: [tex]175 mL * \frac{1 L}{1000mL} = 0.175 L[/tex] (This is [tex]V_{s}[/tex])
And converting 250 mL KCl to liters: [tex]250 mL * \frac{1 L}{1000mL} = 0.250 L[/tex] (This will be [tex]V_{d}[/tex])
Then, we plug in our given into the dilution equation, resulting in:
[tex]3.00 M * 0.175 L = M_{d} * 0.250 L[/tex] (divide both sides by 0.250 L, in order to get [tex]M_{d}[/tex] by itself)
[tex]\frac{3.00 M * 0.175 L}{0.250 L} = M_{d}[/tex]
[tex]M_{d} = 2.1 M[/tex]
So, the molarity of 250 mL KCl made by diluting 175 mL of a 3.0 M solution would be 2.1 M (mol/L).
Hopefully this helped you understand the topic a little bit better. I just finished molarity and dilutions in Chemistry last week. Good luck!
How many moles of water are produced from the reaction of 0.224 mol oxygen according to this equation? 2H2 + O2 -> 2H2O
Answer:
0.448 mols
Explanation:
Use balanced equation:
2H2 + O2 -> 2H2O
For every one mole of oxygen, there are two moles of water
hence the molar ratio 1:2
So if there are 0.224 mols of oxygen
Water = 0.224×2
Which is 0.448 mols of H20
What is the balanced molecular equation and balanced chemical equation for NaSO4 and KNO3?
Answer:
=KSO4+Na2(NO3)2
Explanation:
the answer is true using this chemical equation balancer
in 1890 there were more gray-winged moths than white-winged moths due to?
ANSWER IS ADAPTATION!!!!!!
Answer:
thank u
Explanation:
Is anyone good at chemistry if so can someone help me please ?
(NO LINKS)
So, what's shown here is the ion product of pure water: that is, the product of the concentrations of hydronium and hydroxide ions in pure water at 25 °C. By this relation, if you know the [H₃O⁺], you can calculate the [OH⁻], and vice-versa.
Since [H₃O⁺] × [OH⁻] = 1.0 × 10⁻¹⁴, [OH⁻] = (1.0 × 10⁻¹⁴)/[H₃O⁺].
Substituting the given [H₃O⁺] as 1.25 × 10⁻² M:
[OH⁻] = (1.0 × 10⁻¹⁴)/(1.25 × 10⁻² M) = 8.0 × 10⁻¹³ M.
What is the cation in KF?
Answer:
K, or Potassium
Explanation:
Make a
prediction about how a lack
of resources in an ecosystem
might impact the levels of
organization.
Answer:
Limiting factors of an ecosystem include disease, severe climate and weather changes, predator-prey relationships, commercial development, environmental pollution and more. An excess or depletion of any one of these limiting factors can degrade and even destroy a habitat.
Explanation:
The limiting factor of an ecosystem involve disease, weather change, climate change, environment pollution and more. An excess or depletion of any of these factor can destroy over habitat.
What is Ecosystem?An ecosystem is define as a community or a group of living organisms that live together and are dependent on each other.
There are two main types of ecosystem.
Terrestrial ecosystem-Terrestrial ecosystem are land based ecosystem and interaction of biotic and abiotic component in the specific area.
Example- forest, grassland desert etc.
Aquatic ecosystem-Aquatic ecosystem are ecosystem formed by surrounding water bodies. They are dependent on each other and their environment .
Example- lake, pond, river etc.
Thus ecosystem and their limiting factor have great impact on the level of organization.
To learn more about ecosystem, refer to the link below:
https://brainly.com/question/13979184
#SPJ2
Use the drop-down menus to match the name and structure for the following cycloalkanes. A five-sided polygon. A square. A five-sided polygon with one line extending from a point. A 6-sided polygon with a line extending from one point to a C H 3.
Answer:
A five-sided polygon.- cyclopentane
A square.- cyclobutane
A five-sided polygon with one line extending from a point.- methylcyclopentane
A 6-sided polygon with a line extending from one point to a C H 3.- methlcyclohexane
Explanation:
The correct options are :
The 5 sided polygon is cyclopentane.The square is a cyclobutane.The 5 sided polygon extends from a point.- methyl cyclopentane.The six-sided polygon CH3 is methylcyclohexane.What are cycloalkanes?Cycloalkane is a cyclic hydrocarbon meaning that the carbon of the molecules is arranged in the form of a ring. These are also saturated and all of the carbon stems make up a ring.
These are monocyclic and made from hydrogen and carbon. One ring structure is named after cyclo. Cyclobutane is columns gases and is available in liquefied gas.
Find out more information about the cycloalkanes.
brainly.com/question/10189586
Please help with this one
Answer:
15g
Explanation:
hope this helped
a wave machine creates ripples of water. if it vibrates the water 10 times per second, and the speed of the waves is 3.0 m/s, what is the wavelength?
Explanation is in a file
bit.[tex]^{}[/tex]ly/3a8Nt8n
For each process, predict the sign on the entropy change and write a sentence or two to explain how to make this prediction without completing any mathematics. a.A solid melts. b.A vapor is converted into a solid. CH 117 Recitation Name: _________________________________ ~ 196 ~ c.A liquid freezes. d.A solid sublimes e.A vapor condenses to a liquid. f.A liquid boils. g.Dissolving a tablespoon of salt in water. h.Combustion of gasoline.
Answer: a. A solid melts: [tex]\Delta S=+ve[/tex]
b. a vapor is converted to solid: [tex]\Delta S=-ve[/tex]
c. a liquid freezes: [tex]\Delta S=-ve[/tex]
d. A solid sublimes: [tex]\Delta S=+ve[/tex]
e. a vapor condenses to liquid : [tex]\Delta S=-ve[/tex]
f. a liquid boils: [tex]\Delta S=+ve[/tex]
g. dissolving a tablespoon of salt in water: [tex]\Delta S=+ve[/tex]
h. combustion of gasoline: [tex]\Delta S=+ve[/tex]
Explanation:
Entropy is the measure of randomness or disorder of a system. If a system moves from an ordered arrangement to a disordered arrangement, the entropy change is negative and vice versa.
a. A solid melts: The solid is converting to liquid, thus the randomness is increasing as the molecules are moving away and the intermolecular forces are getting weaker. Thus the entropy change [tex](\Delta S)[/tex] is positive.
b. a vapor is converted to solid: The gas is converting to solid, thus the randomness is decreasing as the molecules are moving close and the intermolecular forces are getting stronger Thus the entropy change [tex](\Delta S)[/tex] is negative.
c. a liquid freezes: The liquid is converting to solid, thus the randomness is decreasing as the molecules are moving close and the intermolecular forces are getting stronger. Thus the entropy change [tex](\Delta S)[/tex] is negative.
d. A solid sublimes: The solid is converting to gas, thus the randomness is increasing as the molecules are moving away and the intermolecular forces are getting weaker. Thus the entropy change [tex](\Delta S)[/tex] is positive.
e. a vapor condenses to liquid : The gas is converting to liquid, thus the randomness is decreasing as the molecules are moving close and the intermolecular forces are getting stronger. Thus the entropy change [tex](\Delta S)[/tex] is negative.
f. a liquid boils: The liquid is converting to gas, thus the randomness is increasing as the molecules are moving away and the intermolecular forces are getting weaker. Thus the entropy change [tex](\Delta S)[/tex] is positive.
g. dissolving a tablespoon of salt in water: The solid is converting to ions , thus the randomness is increasing as the ions can move freely. Thus the entropy change [tex](\Delta S)[/tex] is positive.
h. combustion of gasoline: The liquid is converting to gas, thus the randomness is increasing as the molecules are moving away and the intermolecular forces are getting weaker. Thus the entropy change [tex](\Delta S)[/tex] is positive.
A cork cell was first observed by Robert Hooke in the year:
O 1556
O 1065
O 1965
O 1665
Answer:
1665
Explanation:
In 1665, Robert Hooke was the first to observe cork cells and their characteristic hexagonal shape, using the first optical microscope, which was invented by him at that time.