Answer:
1,2,3
Explanation:
all if these answers are true except for the last one
Answer:1. Energy and matter are both conserved in stars.
2. Energy in stars causes the fusion of light elements
3.Some matter is converted into matter in stars
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2. Question
What makes up all stars?
A: Plasma
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3. Question
The International Astronomical Union(IAU) defines a constellation by its:
A: Boundary
Explanation:
What is the mass in grams of 4.63 mol of C8H18?
Answer: 114.22852 grams
HOPE THIS HELPS
1A: Consider these compounds:
A. PbF2
B. Ni(CN)2
C. FeS
D. CaSO4
Complete the following statements by entering the letter(s) corresponding to the correct compound(s). (If more than one compound fits the description, include all the relevant compounds by writing your answer as a string of characters without punctuation, e.g, ABC.)
Without doing any calculations it is possible to determine that magnesium hydroxide is more soluble than __________, and magnesium hydroxide is less soluble than _______.
It is not possible to determine whether magnesium hydroxide is more or less soluble than_______ by simply comparing Ksp values.
1B: For each of the salts on the left, match the salts on the right that can be compared directly, using Ksp values, to estimate solubilities.
(If more than one salt on the right can be directly compared, include all the relevant salts by writing your answer as a string of characters without punctuation, e.g, ABC.)
1. nickel(II) hydroxide
A. Fe(OH)2
2. silver chloride
B. PbS
C. AlPO4
D. MnS
Write the expression for K in terms of the solubility, s, for each salt, when dissolved in water.
nickel(II) hydroxide
silver chloride
Ksp=_______
Ksp=________
Note: Multiply out any number and put it first in the Ksp expression. Combine all exponents for s.
Solution :
Compound Ksp
[tex]$PbF_2$[/tex] [tex]$3.3 \times 10^{-8}$[/tex]
[tex]$Ni(CN)_2$[/tex] [tex]$3 \times 10^{-23}$[/tex]
FeS [tex]$8 \times 10^{-19}$[/tex]
[tex]$CaSO_4$[/tex] [tex]$4.93 \times 10^{-5}$[/tex]
[tex]$Mg(OH)_2$[/tex] [tex]$5.61 \times 10^{-12}$[/tex]
Ksp of [tex]$Ni(CN)_2 << Ksp \text{ of}\ \ Mg(OH)_2$[/tex] and both compounds dissociate the same way. Hence [tex]$Mg(OH)_2$[/tex] is more soluble than [tex]$(B). \ Ni(CN)_2$[/tex]
[tex]$Mg(OH)_2$[/tex] is less soluble than [tex]$(A). \ \ PbF_2 \ ()Ksp \ PbF_2 > Ksp \ \text{ of } \ Mg(OH)_2$[/tex]
It is not possible to determine CD - [tex]$FeS \text{ or} \ CaSO_4$[/tex] is more or less soluble than [tex]$Mg(OH)_2$[/tex] as though they have a different Ksp values their molecular dissociation is also different and they may have a close solubility values.
[tex]$Ni(OH)_2$[/tex] can be directly compared with PbS, [tex]$AlPO_4, MnS$[/tex]
[tex]$\text{For } \ Ni(OH)_2$[/tex]
[tex]$AB_2(s) \rightarrow A^{2+} + 2B^{-}$[/tex]
[tex]$Ni(OH)_2(s) \rightarrow Ni^{2+} + 2OH^-$[/tex]
100
1-s s 2s
Ksp = [tex][A2+][B-]^2 = s \times (2s)^2 = 4s^3[/tex]
Hence they can be directly compared by Ksp values, smaller the Ksp, smaller the solubility.
For Silver Chloride
[tex]$AB(s) \rightarrow A^{x+}+B^{x-}$[/tex]
[tex]$AgCl(s) \rightarrow Ag^+ + Cl^-$[/tex]
1 0 0
1 - s s s
Ksp [tex]$=[A^{x+}][B^{x-}]=s \times s = s^2$[/tex]
Hence, they can be directly compared by Ksp values, smaller the Ksp, smaller the solubility.
The student then sets up two more test tubes containing iron nails.
Explain why
test tube 1 does not rust because boiled water has no oxygen and oil stops new oxygen from entering and without oxygen iron cannot rust.
test tube 2 does not rust because the drying agent absorbs all the moisture from air, and moisture is required for iron to rust.
In the absence of oxygen or moisture rusting of the nail can not take place.
There are two very important things that must be present for the process of rusting to take place these are;
Oxygen MoistureIf we can exclude these two, rusting will not take place in the absence of either of them.
Rusting does not occur in tube 1 because the water have been boiled and the oxygen removed then it is stored under oil that prevents corrosion.
In tube 2, there is a drying agent that removes moisture from air hence moisture does not have access to the nail so it does not rust.
Learn more about rusting: https://brainly.com/question/4206267
Consider the substances in the reaction: Uranium-235, Krypton-93, and Barium-140. The values of “235”, “93”, and “140” all represent what characteristic of the elements?
Answer:
Relative atomic mass
Explanation:
Why do different parts of the world have such different animals?
Answer:
a
Explanation:
Write the balanced half equation of iron 2 and permanganate in a solution of acid. Show all of your work.
Answer:
5Fe⁺² + MnO₄⁻ + 8H⁺ => 5Fe⁺³ + Mn⁺² + 4H₂O
Explanation:
Fe⁺² + MnO₄⁻ + H⁺ => Mn⁺² + Fe⁺³ + H₂O
5(Fe⁺² => Fe⁺³ + 1e⁻) => 5Fe⁺² => 5Fe⁺³ + 5e⁻
MnO₄⁻ + 5e⁻ => Mn⁺² => MnO₄⁻ + 8H⁺ + 5e⁻ => Mn⁺² + 4H₂O
=> 5Fe⁺² + MnO₄⁻ + 8H⁺ => 5Fe⁺³ + Mn⁺² + 4H₂O
In the graphic,
X represents which element?
40
20
Answer:Ca
Explanation:
Plzzzzzzzzzzzzzzzz help
Answer:
Your correct.
Explanation:
Answer:
The answer is C.
Explanation:
I just know.
does anyone know how many grams of of fe2o3 react to produce 450 grams of fe
Answer:
14.4g
Explanation:
How many molecules are in 4.67 mols of H2O
Answer:
2.81 × 10²⁴ moleculesExplanation:
The number of molecules can be found by using the formula
N = n × L
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
We have
N = 4.67 × 6.02 × 10²³
We have the final answer as
2.81 × 10²⁴ moleculesHope this helps you
How many grams of chlorine gas are needed to make 5.20 x 100 g of a solution that is 2.00 ppm chlorine by mass?
mass:
CI,
Answer:
mass of chlorine = 10.4 grams
Explanation:
Mass of the solution = 5.20 × 10⁶ g
ppm chlorine by mass = 2.00
Recall that:
[tex]ppm = \dfrac{mass \ of \ chorine \ gas (solute)}{ mass of the solution }\times 10^6[/tex]
[tex]2 = \dfrac{mass \ of \ chorine \ gas (solute)}{ 5.20\times 10^6}\times 10^6[/tex]
mass of chlorine = 5.20 × 2.0
mass of chlorine = 10.4 grams
What is the difference between gases and nonmetal?
Answer:
1) some of the gas maybe metal but non metal directly refers it self to not begin metal
2) gases are present in only air . non metals are available in solid form too
molar mass (NH4)2SO4
Answer:
132.15
Explanation:
Molar mass N = 14.00
Molar mass H = 1.01
Molar mass H4 = 1.01 x 4 = 4.04
Molar mass NH4 = 14.00 + 4.04 = 18.04
Molar mass (NH4)2 = 18.04 x 2 = 36.08
Molar mass S = 32.07
Molar mass O = 16.00
Molar mass O4 = 16.00 x 4 = 64.00
Molar mass SO4 = 32.07 + 64.00 = 96.07
Molar mass (NH4)2SO4 = 36.08 + 96.07 = 132.14
In each of the molecules drawn below one chemical bond is colored red. Decide whether this bond is likely to be polar or not. If the bond is likely to be polar, write down the chemical symbol for the atom which will have more negative charge. The highlighted bond is polar and the more negative atom is The highlighted bond is nonpolar. The highlighted bond is polar and the more negative atom is The highlighted bond is nonpolar. The highlighted bond is polar and the more negative atom is The highlighted bond is nonpolar.
The question is incomplete, the complete question is shown in the image attached to this answer
Answer:
See Explanation
Explanation:
I want us to bear something in mind. A compound is polar when there is a considerable difference in electronegativity between two bonding atoms in the molecule.
The implication of this is, the shared electron pair of the bond will be closer to the atom of greater electronegativity than the atom of lesser electronegativity thereby creating a dipole in the molecule.
Let us consider each of the compounds;
For Cl-F, the highlighted bond is polar and F is the more electronegative atom
For H-Br, the highlighted bond is polar and Br is the more electronegative atom
For N≡N, the highlighted bond is nonpolar since it is a homonuclear diatomic molecule.
answer this correctly, only sincere answers please. I really need help. I will do all I can to make someone answer this. Thanks! ASAP
Explain the relationship between pH, POH, hydronium concentration and hydroxide concentration and be prepared to complete the chart below based on the provided knowns.
Complete the chart below based on the provided knowns.
H+ ______x_______
OH - 1 x 10^-11______
pH 3_____________
POH _____y_______
Answer:
See Explanation
Explanation:
Let us recall that;
[H^+] [OH^-] = 1 * 10^-14
Where;
[OH^-] = 1 x 10^-11
Then;
[H^+] = 1 * 10^-14/1 x 10^-11
[H^+] = 1 * 10^-3
pH = -log [H^+]
pH = -log(1 * 10^-3)
pH = 3
Also;
pH + pOH = 14
pOH = 14 - pH
pOH = 14 -3
pOH = 11
what class is sodiumtrioxocarbonate(IV) strong or weak base and why?
Answer:
Strong base
Explanation:
Anhydrous sodiumtrioxocarbonate(IV) Na2CO3 and crystalline sodiumtrioxocarbonate(IV) Na2CO3 are two forms of sodiumtrioxocarbonate(IV) Na2CO3. The Solvay process is the most common name for the sodiumtrioxocarbonate(IV) Na2CO3 production process.
Still, as Na2CO3 reacts, it produces CO3. That tends to be a weak acid's conjugate base. As a result of the removal of H+, carbonic acid was formed (Strong Base)
Pls just help me out the vid is 6 Chemical Reactions That Changed History; need help on no.6. I DON’T EVEN KNOW HOW TO SOLVE IT
Explanation:
HCL you can do it yourself .try again
convert 32 degrees celsius to kelvin
Answer:
305.15
Explanation:
32 celsius converted to kelvin is 305.15 kelvin
Formula
32°C + 273.15 = 305.15K
A chemist has a small amount of compound that has the boiling point 65°c that must be fractionally distilled. Yet, the chemist doesn't want to lose any of the compound to hold up on the column. What the chemist should do?
Answer:
A "chaser," a high-boiling compound whose vapors will displace the vapors of the desired low-boiling compound, can be used to distill a small amount of compound.
A smaller fractionation apparatus or a Vigreux column could be used instead.
Explanation:
A neutral atom with the electron configuration 2-7 would most likely form a bond with an atom having the configuration
Answer:
1s2 2s2
Explanation:
What volume, in milliliters,
Answer:
25.4
Explanation:
PLZ mark me brainlist
12. Convert 1.98 grams of PbSo, to molecules.
No links please
Answer:
3.93 × 10²¹ molecules
Explanation:
Convert 1.98 grams of PbSO₄ to molecules.
Step 1: Given data
Mass of PbSO₄: 1.98 g
Step 2: Calculate the number of moles corresponding to 1.98 g of PbSO₄
The molar mass of PbSO₄ is 303.26 g/mol.
1.98 g × 1 mol/303.26 g = 6.53 × 10⁻³ mol
Step 3: Calculate the number of molecules in 6.53 × 10⁻³ moles of PbSO₄
To convert moles to molecules, we need a conversion factor: Avogadro's number. There are 6.02 × 10²³ molecules of PbSO₄ in 1 mole of molecules of PbSO₄.
6.53 × 10⁻³ mol × 6.02 × 10²³ molecules/1 mol = 3.93 × 10²¹ molecules
In the covalent compound CH3, the Greek prefix used to represent the anion is Answer here
Answer:
Tri.
Explanation:
''Tri'' is the Greek prefix used to represent the CH3 because there are three hydrogen atoms to form the covalent compound so in Greek method ''Tri'' is used for three. In Greek system, there are certain names for prefixes such as ''di'' is used for two, ''tri'' is used for three, ''tetra'' is used for four etc. This method only provides information about the number of atoms that form the covalent compound.
Given the following information: SO2(g) + 12 O2(g) = SO3(g) Kp = 2.5E-2 What is the Kp value for the following reaction: 2 SO2(g) + O2(g) = 2 SO3(g)
Answer:
K = 6.25x10⁻⁴
Explanation:
Based on the reaction:
SO₂ + 1/2 O₂ ⇄ SO₃ Kp = 2.5x10⁻²
We can find the Kp of a similar reaction using Hess's law where the sum of 2 reactions a and b produce a K that is:
K = Ka*Kb
The sum of twice the reaction of the problem:
SO₂ + 1/2 O₂ ⇄ SO₃
+ SO₂ + 1/2 O₂ ⇄ SO₃
2SO₂ + O₂ ⇄ 2SO₃
Where K must be:
K = Kp*Kp = Kp²
K = (2.5x10⁻²)²
K = 6.25x10⁻⁴what is the difference between diffusion and osmoses
Answer:
Diffusion means that particles travel from a higher concentration to a lower concentration region before balance is achieved. The semi-permeable membrane is present in osmosis, so that only solvent molecules can travel freely to equalize the levels.
How many moles of CH2 must react in order to produce 50 moles
TRUE OR FALSE?
The reason for forming multiple bonds is an interaction of end to end type between unhybridized p orbitals.
20 points!
Answer:
I think its false
Explanation:
A solution has a pH of 10.
What is the concentration of hydrogen ions?
Please solve I will give brainliest to correct answer
Answer:
-846 kJ
Explanation:
Using Henderson Hasselbach's law,
2Al + 3/2 O2 -> Al2O3 H = -1670 kJ
-(2Fe + 3/2 O2 -> Fe2O3) = Fe2O3 -> 2Fe + 3/2 O2 H = 824 kJ
-1670 kJ + 824kJ = -846 kJ
How many grams of NiNi are formed from 55.3 g55.3 g of Ni2O3Ni2O3?
2Ni2O3(s)⟶4Ni(s)+3O2(g)2Ni2O3(s)⟶4Ni(s)+3O2(g)
Step 1: Show the strategy for solving this problem.
You are currently in a labeling module. Turn off browse mode or quick nav, Tab to items, Space or Enter to pick up, Tab to move, Space or Enter to drop.
grams Ni2O3⟶⟶⟶grams Nigrams Ni2O3⟶⟶⟶grams Ni
Answer Bank
grams O2O2
moles NiNi
grams NiNi
moles Ni2O3Ni2O3
moles O2O2
grams Ni2O3Ni2O3
Answer:
110.92 g
Explanation:
Amount of Ni2O3 consumed= 55.3/59 =0.94 moles
From the reaction equation;
2 moles of Ni2O3 yields 4 moles of Ni
0.94 moles yields 0.94 moles * 4/2
= 1.88 moles of Ni2O3
Mass of 1.88 moles of Ni2O3 = 1.88 moles of Ni2O3 * 59 gmol-1 = 110.92 g