Answer:
a reaction in which one element is substituted for another element in a compound
Explanation:
Suggest two reasons for the change in the carbon dioxide percentage from 1900 to 2015.
Answer: 43
Explanation:
TRUE or FALSE. Write I If the statement is TRUE, write F if the statement is
FALSE on the space provided before the number.
1. A mixture is always made up of a combination of elements
2. A mixture is not a chemical combining of substances
3. In a mixture, the substances lose their identities
4. The substances involved in a mixture cannot be separated by a simple physi
process
5. Salt and water can be separated through distillation
6. Water for drinking can only be obtained from seawater by distillation
7. The distillation of miscible liquids is only possible if the liquids have differ
boiling points.
8. Mixtures have fixed melting and boiling points.
9. Paper chromatography is a physical method for separating mixtures
10. Crude oil is broken down by heat, vaporized, and allowed to condense
various liquids such as gasoline. This process is called distillation
What is Aurora Borealis?
Auroras present in polar regions.
Answer:
the Northern Lights
Explanation:
The northern lights, one of several astronomical phenomena called polar lights (aurora polaris), are shafts or curtains of colored light visible on occasion in the night sky. Aurora borealis
hope this helps
Explain the process of how James Chadwick
found the neutron.
Answer:
In 1932, the physicist James Chadwick conducted an experiment in which he bombarded Beryllium with alpha particles from the natural radioactive decay of Polonium. The resulting radiation showed high penetration through a lead shield, which could not be explained via the particles known at that time.
Explanation:
60 points! please help me! will appreciate it!
Answer:
[tex]\huge\boxed{\sf 49.41\ L}[/tex]
Explanation:
In the reaction:
for every 3 moles of H₂, 2 moles of NH₃ are produced.
Converting 25 g of Ammonia into moles:
Moles = mass / molar mass
= 25 / (14 + 1 × 3)
= 25 / (14 + 3)
= 25 / 17
= 1.47 mol
From the reaction:
2 NH₃ = 3 H₂
1 NH₃ = 3/2 H₂
1 NH₃ = 1.5 H₂
1.47 mol of NH₃ = 1.5 × 1.47 mol of H₂
1.47 mol of NH₃ = 2.2 mol of H₂
So, 2.2 mol of H₂ are needed to produce 1.47 mol (25 g) of NH₃
Converting 2.2 mol of H₂ into L:
= mole × molar value
[molar value = 22.4 L/mol]
= 2.2 × 22.4
= 49.41 L
[tex]\rule[224]{225}{2}[/tex]
Raisin bran is a
O homogenous mixture
O compound
O heterogeneous mixture
O element
Answer:
It is a heterogeneous mixture
PLEASE ANSWER AND I WILL GIVE BRAINLIEST! THE ANSWER IS NOT B
Scientists have changed the model of the atom as they have gathered new evidence. One of the atomic models is shown below.
A large black cross in a purple circle with a black line around the purple, with 10 small green balls dispersed within the purple circle.
What experimental evidence led to the development of this atomic model from the one before it?
A. A few of the positive particles aimed at a gold foil seemed to bounce back.
B. The colors of light emitted from heated atoms had very specific energies.
C. Equations were used to identify regions around the nucleus where electrons would likely be.
D. Cathode rays were bent in the same way whenever a magnet was brought near them.
Answer:
A
Explanation:
It says it in the videos my sister watch on Edgenuity. A few of the positive particles aimed at a gold foil seemed to bounce back. If you take notes it says it. (ps. I am not trying to be mean I am just saying- no hurt feelings?)A scuba diving tank at a pressure of 180 atmospheres contains a mixture of three gases: oxygen, helium, and nitrogen. The partial pressures of the oxygen and helium are 81 atmospheres and 58 atmospheres, respectively. What is the partial pressure of nitrogen in the tank?
Considering the Dalton's partial pressure, the partial pressure of nitrogen in the tank is 41 atm.
Dalton's partial pressureThe pressure exerted by a particular gas in a mixture is known as its partial pressure.
So, Dalton's law states that the total pressure of a gas mixture is equal to the sum of the pressures that each gas would exert if it were alone:
[tex]P_{T} =P_{1} +P_{2} +P_{3} + ... +P_{n}[/tex]
where n is the amount of gases present in the mixture.
This relationship is due to the assumption that there are no attractive forces between the gases.
In summary, the total pressure in a mixture of gases is equal to the sum of partial pressures of each gas.
Partial pressure of nitrogenIn this case, the total pressure of the gas mixture is calculated as:
[tex]P_{T} =P_{oxygen} +P_{helium} +P_{nitrogen}[/tex]
You know that:
[tex]P_{T} = 180 atm[/tex][tex]P_{oxygen} = 81 atm[/tex][tex]P_{helium} = 58 atm[/tex][tex]P_{nitrogen}= ?[/tex]Replacing in the expression for the total pressure:
[tex]180 atm=81 atm+58 atm+P_{nitrogen}[/tex]
Solving:
180 atm -81 atm -58 atm= [tex]P_{nitrogen}[/tex]
41 atm= [tex]P_{nitrogen}[/tex]
Finally, the partial pressure of nitrogen in the tank is 41 atm.
Learn more about Dalton's partial pressure:
brainly.com/question/25181467
brainly.com/question/14119417
Nitrogen gas and hydrogen gas react to produce ammonia according to the following equation.
N2 + 3H2 → 2NH3
Which ratio of components is correct?
A For every mole of hydrogen gas, the reaction produces 2 moles of ammonia.
B For every 3 moles of hydrogen gas, the reaction produces 2 moles of ammonia.
C For every 2 moles of nitrogen gas, the reaction requires 3 moles of hydrogen gas.
D For every mole of nitrogen gas, the reaction produces 1 mole of ammonia. ***
The answer will be for every 3 moles of hydrogen gas, the reaction produces 2 moles of ammonia.
What will be the ratio of nitrogen and hydrogen to produce ammonia?
For making ammonia one mole of nitrogen gas is combined with the three moles of hydrogen gas to produce two moles of ammonia.
The ratio of nitrogen, hydrogen, and ammonia is as follows 1:3:2. now if we need to produce 10 moles of ammonia for the balanced equation the ratio will become 10:30:20.
The reaction is as follow:-
[tex]\rm N_2+3H_2----- > 2NH_3[/tex]
For nitrogen
[tex]\rm N_2--- > 1\ Molecule \\\rm N_2--- > 1\ Mole\\\rm N_2--- > 28.02\ g[/tex]
For Hydrogen
[tex]\rm H_2--- > 3\ Molecules\\\rm H_2--- > 3\ Moles\\ \rm H_2--- > 3\times2.02--- > 6.06\ g[/tex]
For Ammonia
[tex]\rm NH_3--- > 2\ Molecules \\\rm NH_3--- > 2\ Moles\\\rm NH_3--- > 2\times17.04--- > 34.08\ g[/tex]
Thus the answer will be for every 3 moles of hydrogen gas, the reaction produces 2 moles of ammonia.
To know more about Balancing chemical equations follow
https://brainly.com/question/16031275
Answer:
B For every 3 moles of hydrogen gas, the reaction produces 2 moles of ammonia.
Explanation: I just did it
Please help me!!!!!!!!! i'll mark you B
Answer:
11) time
9) a projectile
5) Greater than vx
13)
A sample of substance X is found to be an element with the atomic number 13.
Which atomic number below represents an element that shares similarities with
substance X?
A.3
B.5
C.22
D.33
(i think it’s b but i’m not sure)
Atoms of different element can not have same atomic number because only same type of atoms combine to form element. Atoms belonging to different element can have different atomic number. Therefore, the correct option is option B.
What is element?Element generally consist of atoms or we can atoms combine to form element. Atoms of an element is always same, means all the properties of all atoms of one type of element is same. Two or more than two atoms with different physical or chemical properties can not combine together to form an element.
Element with atomic number 13 represents aluminium element. The element that belongs to aluminium family will have same property as aluminium. Boron is a element that have same property as aluminium.
Therefore, the correct option is option B.
To know more about element, here:
https://brainly.com/question/8460633
#SPJ2
The standard reduction potentials for two half-cells involving iron are: given below. Fe2+ (aq) + 2e– ® Fe (s) Eο = –0.44 V Fe3+ (aq) + e– ® Fe2+ (aq) Eο = +0.77 V What is the equation and the cell potential for the spontaneous reaction that occurs when the two half-cells are connected?
Answer:
Explanation:
Fe⁺² (aq) + 2e⁻ = Fe (s) ; E⁰ = - .44 V
Fe⁺³ (aq) + e⁻ = ® Fe²⁺ (aq) ; E⁰ = + .77 V
Reduction potential of second reaction is more , so it will take place , ie Fe⁺³ will be reduced and Fe will be oxidised .
So reaction in the combined cell will be
2Fe⁺³ + Fe = 3Fe⁺²
cell potential = .77 - ( - .44 )
= 1.21 V .
URGENT
What do electrochemical cells use to generate electricity?
Question 1 options:
Flow of protons
Flow of neutrons
Flow of electrons
Flow of particles
Answer:
flow of electrons between the electrolytes and the electrodes
Decide if these characteristics belong to the Protons, neutrons or Electrons.
1) They spin around the nucleus. _____
2) They are located in the orbits. _____
Answer:
1)electrons
2)protons, neutrons
Explanation:
please mark me as brainlest
Answer:
1 . c
2. a , b
Explanation:
1 . the electrons spin around the nucleus of an atom
2. the protons and neutrons are located in the orbit of an atom
PLEASE HELP ASAP The concentration of a solution is equal to the mass of solute divided by the volume of solvent. Units of concentration are grams per 100 milliliters, g/100 mL. You add 12g of sugar to 100 mL of water. What is the concentration?
. 12 g/100mL
12 g/100mL
12g
120g
Answer:
120 g is the answer I think
4) Find the mass of 1.46 mol of Al2(SO4)3.
Answer:
1.46mol of Al2(SO4)3 weights 499.5 grams
Explanation:
First we will find the gram formula mass of Al2(SO4)3.
Al * 2 = 26.98 g/mol * 2 = 53.96 g
SO4 * 3 = 96.06 g/mol * 3 = 288.18
53.96 + 288.18 = 342.14 g
That is the mass of 1 mol of AL2(SO4)3.
Now we will multiply 342.14g by 1.46.
342.14 * 1.46 = 499.5244 g
Or ... 499.5 g
If you had a jar of cream and shook it up does the jar weigh the same
Hell me ASAP please
The electronic configuration of an element is given below.
Element 1: 1s22s22p4
Which statement about the reactivity of the element is true?
It is reactive because it has to gain an electron to have a full outermost energy level.
It is unreactive because it has to lose an electron to have a full outermost energy level.
It is reactive because it has to gain two electrons to have a full outermost energy level.
It is unreactive because it has to gain two electrons to have a full outermost energy level.
Please Help. Will Mark Brainliest
Answer:
It is reactive because it has to gain an electron to have a full outermost energy level.
Explanation:
The electron configuration of oxygen is 1s2,2s2 2p4.
Oxygen is in group six in the periodic table so it has six electrons in its valence shell. This means that it needs to gain two electrons to obey the octet rule and have a full outer shell of electrons (eight).
The law of conservation of matter tells us that the total number of atoms does not change in a chemical reaction and thus mass is conserved. Select ALL of the reactions that obey the law of conservation of matter. A) 4 NH3 + 5 O2 → 4 NO + 6 H2O B) 8 H2S + 8 Cl2 → S8 + 16 HCl C) CH4 + 2 O2 → CO2 + H2O D) HCl + K2CO3 → KCl + H2O + CO2 E) 2 Al(OH)3 + 3 H2SO4 → Al2(SO4)3 + 6 H2O
A B & E
If you look at the balancing you'll see that C & D are balanced incorrectly.
The reactions A, B, and E follow the law of conservation of mass. So the correct options are A, B, and E.
What is the law of conservation of mass?According to the rule of conservation of mass, matter cannot be generated or destroyed in a closed or isolated system. It is preserved yet capable of changing forms.
The rule of conservation of mass, which applies to the study of chemistry, states that the mass of the reactants and products in a chemical reaction must be equal.
To be clear: A system that is isolated from its environment is one that does not interact with it. As a result, no matter what changes or chemical reactions take place in that isolated system, the mass will remain constant; even if the final state may differ from the initial state, there can be no more or less mass than there was before the change or reaction.
Therefore the correct options are A, B, and E.
Read more about the law of conservation of mass, here
https://brainly.com/question/13383562
#SPJ2
Which type of energy warms Earth’s surface?
Answer:
infared radiation
Explanation:
Answer:
infared radiation
Explanation:
) The atomic number of magnesium is 12.
Magnesium exists as three isotopes; Magnesium-24, Magnesium-25 and Magnesium 26.
Describe, by reference to the numbers of subatomic particles, the differences between one atom of
each of these isotopes.
(2)
Answer: The difference between these 3 isotopes is the number of neutrons.
The atomic mass of an atom is the number of protons plus neutrons. We know that the atomic number of magnesium is 12, so therefore there are 12 protons.
In Magnesium-24, there are 24-12 neutrons = 12 neutrons.
In Magneusium-25, there are 25-12 neutrons = 13 neutrons
In Magnesium-26, there are 26-12 neutrons = 14 neutrons
For an atom (which is neutral), which of these must be
true?
The number of protons is equal to the number of electrons
The atomic number is equal to the mass number
The number of electrons is equal to the number of neutrons
The number of protons is equal to the number of neutrons
Answer:
The number of protons is equal to the number of electrons
Explanation:
For an atom to be neutral, all the charges have to equal zero. Because protons are charged +1 and electrons are charged -1, the number of protons has to be equal to the number of electrons for the charges to cancel out.
What’s the answers ???
Answer:
1.potential
2. Kinetic
3. Potential
4. I think is potential because it is storing the energy but if is a crank flashlight it is kinetic.
Explanation:
Gasoline, if 9.00 liters has a mass of 6120 g. Find the density in g/cm^3
Answer:
The density of gasoline is 0.68 g/cm³.
Explanation:
Given data:
Volume of gasoline = 9.00 L
Mass of gasoline = 6120 g
Density of gasoline = ?
Solution:
first of all we will convert the unit, L to mL.
9.00 L × 1000 mL / 1 L = 9000 mL
Formula:
d = m/v
d = density
m = mass
v= volume
d = 6120 g/ 9000 mL
d = 0.68 g/cm³ ( mL =cm³ )
Thus, density of gasoline is 0.68 g/cm³ .
Which of the following is an ozone depleting substance (ODS)?
a.
ultraviolet radiation
b.
chlorofluorocarbon (CFC)
c.
biogeochemical cycle
d.
none of the above
Answer:
b
Explanation:
In an ecosystem, the ozone depleting substance is chlorofluorocarbon or the CFC's.
What is an ecosystem?Ecosystem is defined as a system which consists of all living organisms and the physical components with which the living beings interact. The abiotic and biotic components are linked to each other through nutrient cycles and flow of energy.
Energy enters the ecosystem through the process of photosynthesis .Animals play an important role in transfer of energy as they feed on each other.As a result of this transfer of matter and energy takes place through the system .Living organisms also influence the quantity of biomass present.By decomposition of dead plants and animals by microbes nutrients are released back in to the soil.There are different types of ecosystems.
Learn more about ecosystem,here:
https://brainly.com/question/1673533
#SPJ6
Is the car moving backwards between D and F? Explain your answer.
Answer:
No
Explanation:
This is velocity time graph .
See the change between D and E(F is not given).
The graph goes up means velocity is up If it is going back then the velocity should be on negative side i.e beneath 0.round 42,561 to 4 significant figures
Answer:
4,256
if not that then 42,560
Explanation:
What trend does electronegativity follow, going down the periodic table?
A. Electronegativity increases because there are more total electrons
in the atom.
B. Electronegativity increases because there are more valence
electrons in the atom.
C. Electronegativity decreases because the valence electrons are
farther from the nucleus.
D. Electronegativity decreases because the size of the nucleus is
bigger.
Electronegativity decreases because the valence electrons are farther from the nucleus. Hence, option C is correct.
What is electronegativity?Electronegativity is a chemical property that describes the tendency of an atom or a functional group to attract electrons toward itself.
From top to bottom down a group, electronegativity decreases. This is because atomic number increases down a group, and thus there is an increased distance between the valence electrons and nucleus, or a greater atomic radius.
Important exceptions to the above rules include the noble gases, lanthanides, and actinides.
Electronegativity decreases because the valence electrons are farther from the nucleus. Hence, option C is correct.
Learn more about Electronegativity here:
https://brainly.com/question/13557134
#SPJ2
3. What enables electrons to move from NADH or FADH2 to complex I, to the other complexes, to molecular oxygen
It's too short. Write at least 20 characters to explain it well.
Your answer can't be empty