Answer: C. Electrochemical cells involve oxidation-reduction reactions.
Explanation: Oxidation occurs at the anode, and reduction occurs at the cathode.
True or False: Once the formulas for the reactants and the products are determined, the subscripts may not be changed.
Answer:
true
Explanation:
tvyvyvtvtvtbbtbb
Calcium carbonate decomposes into
calcium oxide and carbon dioxide.
The mass of calcium carbonate that
decomposes is 57 g. At the end of
the experiment, the mass of the
products were only 45 g. What can
we conclude from this information?
Answer:
The mass of carbon dioxide formed is 12g.
Which ion concentration does the pH scale measure? How long is the scale?
Can someone please help me with the right answer? I only have one more attempt :(
Explain your observations in term of how tempurature affects paritcle motion and how liquid changes to a solid
Answer:
See explanation
Explanation:
Temperature is defined as a measure of the average kinetic energy of the molecules of a body.
When a substance is heated, the kinetic energy of its molecules increases as the temperature increases; hence the particles of the substance moves faster with increasing temperature.
When heat is withdrawn from a liquid, the temperature decreases and the average kinetic energy of the molecules decreases. The molecules become less energetic hence the liquid changes into solid
HELP 50 POINTS IF YOU DO IT RIGHT NOW
How much energy is released when 944.3 g of phosphoric acid is produced
P4O10(g) + 6H20(l) -- > 4H3PO4(aq)+424 kj
Answer:
1024.84 Kj
Explanation:
P₄o₁₀(g) + 6H₂O(l) => 4H₃PO₄(aq) + 424Kj
moles H₃PO₄ = (944.3g H₃PO₄) /(97.994g H₃PO₄ /mole H₃PO₄)
= 9.64 moles H₃PO₄
From equation reaction ratios ...
4 moles H₃PO₄ => 424 Kj
9.64 moles H₃PO₄ => (?)
4 moles H₃PO₄/9.64 moles H₃PO₄ = (424Kj)/(?)
Energy Released (Kj) = (424Kj)(9.64moles)/(4moles) = 1021.84 Kj
If peanut butter wasn't called peanut butter.. what would it be called?
Answer:
I have no idea
Explanation:
A solute can be obtained from a solution by...
Answer:
Evaporating the solvent
Explanation:
What is defined as the plants and animals and the physical surroundings, including the sun, air, soil, and water?
Answer:
Ecosystem
Explanation:
The answer is ecosystem because the ecosystem includes the community such as living things and the enviornment of nonliving things such as the sun!
Answer:
ecosystem I'm pretty sure
Please help :)
It’s a science thing for 7th grade
Answer: The first question is chemical The second one is Physical
Explanation:
What is a mole of something? Why do scientists use the concept of a mole?
Answer: A mole is a chemical unit to measure mass of substance.
Explanation:
A mole can be defined as 6.02214076 × 1023 of atoms, ions, molecules and others. A mole is the total amount of discrete entity within a substance present in the form of atoms, ions, and molecules. As atoms, ions, molecules are small entities within any substance so it is necessary to measure each of them and recognize them so the scientists development the concept of mole. It is the convenient unit of measurement because of the presence of greater number of molecules, atoms, and ions present in any substance.
Answer:
The mole is an SI unit used to measure the amount of any substance. One mole is exactly 6.02214076×10 23 particles.
Explanation:
The concept of the mole is important for scientists because it means that one mole of any element has exactly the same number of atoms as one mole of any other element. This information allows chemists to count atomic particles for even very complex chemistry formulas and reactions.
Bob sees some water droplets on the outside surface of a glass of lemonade. What process of the water cycle explains this?
A. condensation
B. evaporation
C. precipitation
D. transpiration
Answer:
es la a porque ay está condensación por
How do you explain the ability of nonmetals to attract electrons to themselves?
Answer:
When these chemical bonds form, atoms of some elements have a greater ability to attract the valence electrons involved in the bond than other elements. Electronegativity is a measure of the ability of an atom to attract the electrons when the atom is part of a compound. Electronegativity differs from electron affinity because electron affinity
HOPE IT HELPS
Explanation:
Answer:
it is electronegativity and it increases as you move up and to the right on the periodic table and nonmetals are situated to the top right of the periodic table
Explanation:
Just help please
And does anybody know Johnny from NCT
science:my chosen place is bonifacio global city
i choose this place because?
Answer:
Rewrite the following sentence in reported speech
The chair person said,"A hearty welcome to all present!"
Can someone double check my work? (Ideal Gas Law Equation)
I am solving for the amount of moles in two gases.
For one, it was 4.75mL at 0.5C (273.65K) and 1.2atm.
n=(1.2*4.75)/(0.0821/273.65)=(5.7/22.456)=0.25361653 moles
For the other gas, it was 4.6mL at 0.5C and 1.2atm.
n=(1.2*4.6)/(0.0821/273.65)=(5.52/22.456)=0.24581403 moles
Please double check these for any errors in math or whatever. Thank you.
I did not see any errors, i may be wrong but what i can see is that it is correct
NH₄⁺(aq)+NO₃⁻(aq) → NH₄NO₃(s)
How much energy is released when 3 moles of NH₄+ react?
1) -25.69 kJ
2) -51.38 kJ
3) -77.07 kJ
4) -102.76 kJ
is it true or false?
Answer:
The rainforest is teeming with animals and insects, so you would hear humming. Frogs and birds make some of the loudest rainforest sounds.
howler monkeys, are the loudest so i think that its false cause lost of animals are there but some can be quiet
0.53g of acetanilide was subjected to kjeldahl determination and the ammonia produced was collected in 50cm3 of 0.50M of h2so4.on dilution 250cm3, the acid was titrated against 25cm3 portion of 0.05M sodium carbonate solution. 13.60 of acid was required for each titration. What is percentage of nitrogen in acetanilide
Answer:
10.57% of N in acetanilide
Explanation:
All nitrogen in the sample is converted in NH₃ in the Kjeldahl determination. The NH₃ reacts with H₂SO₄ as follows:
2NH₃ + H₂SO₄ → 2NH₄⁺ + SO₄²⁻
The acid in excess in titrated with Na₂CO₃ as follows:
Na₂CO₃ + H₂SO₄ → Na₂SO₄ + H₂O + CO₂
To solve this question we must find the moles of sodium carbonate = Moles of H₂SO₄ in excess. The added moles - Moles in excess = Moles of sulfuric acid that reacts:
Moles Na₂CO₃ anf Moles H₂SO₄ in excess:
0.025L * (0.05mol / L) = 1.25x10⁻³ moles Na₂CO₃ / 0.01360L =
0.09191M * 0.250L = 0.0230 moles H₂SO₄ in excess.
Moles H₂SO₄ added:
0.050L * (0.50mol / L) = 0.0250 moles H₂SO₄ added
Moles that react:
0.0250 moles - 0.0230 moles = 0.0020 moles H₂SO₄
Moles of NH₃ = Moles N:
0.0020 moles H₂SO₄ * (2mol NH₃ / 1mol H₂SO₄) = 0.0040 moles NH₃ = Moles N
mass N and mass percent:
0.0040 moles N * (14g / mol) = 0.056gN / 0.53g * 100 =
10.57% of N in acetanilideSulfuric acid reacts with aluminum hydroxide by double replacement producing aluminum sulfate and water Write chemical reaction. If 30 g of sulfuric acid reacts with 25 g of aluminum hydroxide, identify the limiting reactant?
Answer: [tex]H_2SO_4[/tex] is the limiting reagent.
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
The balanced chemical equation is:
[tex]3H_2SO_4(aq)+2Al(OH)_3(aq)\rightarrow Al_2(SO_4)_3(aq)+6H_2O(l)[/tex]
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of} H_2SO_4 =\frac{30g}{98g/mol}=0.31moles[/tex]
[tex]\text{Moles of} Al(OH)_3=\frac{25g}{78g/mol}=0.32moles[/tex]
According to stoichiometry :
3 moles of [tex]H_2SO_4[/tex] require = 2 moles of [tex]Al(OH)_3[/tex]
Thus 0.31 moles of [tex]H_2SO_4[/tex] will require=[tex]\frac{2}{3}\times 0.31=0.21moles[/tex] of [tex]Al(OH)_3[/tex]
Thus [tex]H_2SO_4[/tex] is the limiting reagent as it limits the formation of product and [tex]Al(OH)_3[/tex] is the excess reagent.
Name
12. A chemist places a piece of solid magnesium in an aqueous solution of copper (II)
sulfate and notices a reaction. Pieces of solid copper dropped out of the solution as a
precipitate and magnesium sulfate was formed.
a) Give a balanced formula equation (with state symbols) for this reaction (3 marks)
Answer:
Explanation: Mg(s) + CuSO4 (aq) -> Cu(s) + MgSO4 (aq)
what is the mass number for an atom that has 36 protons 36 electrons and 40 neutrons
Answer:
76
Explanation:
Mass number = number of protons plus the number of neutrons
So, 36 + 40 = 76
If an atom the atomic number 10 and the mass number 12, how many VALENCE electrons does it have?
What happens to pressure if temperature increases? Pressure increases. Pressure stays the same. Pressure decreases. Temperature has no effect on pressure.
Answer:
Pressure increases
Explanation:
According to Gay-Lussac's law, the pressure of a given amount of gas is directly proportional to the temperature at a given volume i.e.
[tex]P\propto T[/tex]
It means the relationship between the pressure and the temperature is direct.
If the temperature increases, the pressure of the gas also increases. Hence, the correct option is (A).
please help i genuinely don’t know what to do
object with a mass of 30 kg is observed to accelerate at the rate of 4 m/s2. Calculate the force required
HELP ASAP !!! PLS ITS DUE IN LIKE 4 MINUTES
Answer:
they have the same structures in common
Height
O
Genetic
O Environmental
O Both
Answer:
its both because your hight can change if u do exercises
Hope it helped.
During the chemical reaction given below 21.71 grams of each reagent were allowed to react. Determine how many grams of the excess reagent are left over after the reaction is complete. 2SO2()+O2()⟶2SO3()
Answer: 16.32 g of [tex]O_2[/tex] as excess reagent are left.
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of} SO_2=\frac{21.71g}{64g/mol}=0.34mol[/tex]
[tex]\text{Moles of} O_2=\frac{21.71g}{32g/mol}=0.68mol[/tex]
[tex]2SO_2(g)+O_2(g)\rightarrow 2SO_3(g)[/tex]
According to stoichiometry :
2 moles of [tex]SO_2[/tex] require = 1 mole of [tex]O_2[/tex]
Thus 0.34 moles of [tex]SO_2[/tex] will require=[tex]\frac{1}{2}\times 0.34=0.17moles[/tex] of [tex]O_2[/tex]
Thus [tex]SO_2[/tex] is the limiting reagent as it limits the formation of product and [tex]O_2[/tex] is the excess reagent.
Moles of [tex]O_2[/tex] left = (0.68-0.17) mol = 0.51 mol
Mass of [tex]O_2=moles\times {\text {Molar mass}}=0.51moles\times 32g/mol=16.32g[/tex]
Thus 16.32 g of [tex]O_2[/tex] as excess reagent are left.
4. A girl walked for 30 minutes. She noticed that she traveled farther in the first 15 minutes of
her walk than in the second 15 minutes,
What can she conclude about her walk?
A she walked over many hills
B
her average speed was faster during the first part of her walk
C. she walked in two different directions
D. she was walking at a constant speed