Answer:
Explanation:
so u can work out the amount of moles of S8 by using
moles=mass/mr
=16/32.1=0.498moles
then use the molar ratio of
S : Fe
1:1 so the moles of Fe is the same 0.498
The use the equation
mass = mr x moles
=55.8 x 0.498
=27.78
so 27.8 g
hope this make sense :)
HELP PLEASE!!!!!
Can someone please help me I should submit it today and the answer should be as paragraph
Answer:
National fire protection Association
Explanation:
the nfpa is a global self funded nonprofit orgnazation establised in 1896 devoted to eliminating death injury protery loss and ecomomic loss due to fire and electrical hazards
The atomic particle with a charge of -1.6 x 10-19 C is
Explanation:
Proton +1.60 x 10-19 C 1.672 x 10-24 g
Electron -1.60 x 10-19 C 9.05 x 10-28 g
Neutron neutral 1.674 x 10-24 g
if The difference in height of mercury in the two arms is 435 mm. What is the pressure of the nitrogen gas in kPa?
Answer:
Therefore, Pnitrogen=97.5kpa
Explanation:
100.0-2.49
=97.5
435= i don't know
what is the relationship between Celsius scale and Kelvin scale of temperature ? very sort answer
Answer:
Celsius + 273 = Kelvin
Explanation:
Density is the ratio of a sample's mass to its volume. A bar of lead has a mass of 115.2 g. When it is submerged in 25.0 mL of water in a graduated cylinder, the water level rises to 35.5 mL. What is the density of the lead
Answer:
[tex]$10.97 \ g/cm^3$[/tex]
Explanation:
Given :
Mass of a bar of lead = 115.2 g
Initial water level [tex]$\text{in the graduated cylinder}$[/tex] = 25 mL
Final water level [tex]$\text{in the graduated cylinder}$[/tex] = 35.5 mL
Difference in the water level = 35.5 - 25
= 10.5 mL
= [tex]10.5 \ cm^3[/tex]
We know that when a body is submerged in water, it displaces its own volume of water.
Therefore, the volume of the lead bar = volume of the water displaced = 10.5 mL = [tex]10.5 \ cm^3[/tex]
We know that mathematically, density is the ratio of mass of body to its volume.
Density of the lead bar is given by :
[tex]$\rho =\frac{\text{mass}}{\text{volume}}$[/tex]
[tex]$\rho =\frac{\text{115.2 g}}{\text{10.5 cm}^3}$[/tex]
= [tex]$10.97 \ g/cm^3$[/tex]
Practice by predicting what would happen if the following underwent alpha decay: (2 points each)
i. Radium-226 ________+ _____
ii. Plutonuim-240 __________+ _____
iii. Uranium-238 __________+ _____
Answer:
See explanation and image attached
Explanation:
During alpha decay, the mass number of the daughter nucleus is less than that of the parent nucleus by 4 units while the atomic number of the daughter nucleus is less than that of the parent nucleus by two units.
Hence, the daughter nucleus is found two places before the parent in the periodic table.
The alpha decay of the species shown in the question are described in the image attached to this answer.
what is the correct symbol for the element copper
Answer:
the correct symbol for copper is:CUAnswer:Cu
Explanation
First letter is usually capital then the other letters are usually in small letters
Which represents the correct equilibrium constant expression for the reaction below?
Answer:
b
Explanation:
because it is products /reactants :)
PLZ Answer ASAP
I need help with this thank you if you get it right
Answer:
A) -277.6 KJ/mol
Explanation:
The enthalpy data for first equation is not given but it should be somewhere around ΔH = –1367 kJ/mol.
So, Basically you want to rearrange the given three equations to match the equation they want you to have. To get the final equation, reverse reaction first reaction (turn its value into positive), multiply second equation by 2, multiply third equation by 3 and you add em all up:
You get 1367 + (2* -393.5) + (3 * -285.8) ~ -277.6 KJ/mol
Which is equal to a temperature of 50°F?
Answer:
10⁰C
Explanation:
10⁰C is equal to 50⁰F
True or false
Bases will have a relatively high concentration of hydroxide ions and a pH around 10.
Answer:
false
Explanation:
It is because the pH for Hydroxide ions is 7
Answer:
True
Explanation:
Acids have a low concentration of hydroxide ions and a pH of 1-6, while bases have a high concentration of hydroxide ions and a pH of 8-14
Explain why a random copolymer is obtained when 3,3-dimethyl-1-butene undergoes cationic polymerization.
Solution :
In the field of chemistry, the cationic polymerization is a kind of the chain growth polymerization where the cation initiator transfers the charge to the monomer and makes it more reactive. This kind of polymerization reaction is very sensitive to the temperature. With increase in temperature, the molecular weight as well as the reaction rate decreases rapidly.
Thus in the cationic polymerization of the 3,3-dimethyl-1-butene, the carbonation intermediate is formed and it rearranges itself. The attack o the 2nd alkene ca take place both the carbonations, so that random copolymer is formed.
How many tons are contained in 825 megagrams?
Answer:909
Explanation:
Write the reaction of maleic acid with Br2
Why should a science teacher know how to prepare stock solution
Answer:
because they were thought in college
Explanation:
hope that helps
What is the function of a lyase enzyme?
a. To assist the substrate by binding to the enzyme, enabling substrate to active site engagement
b. To facilitate a reaction of one substrate to form two products with the use of water
c. To facilitate a reaction of one substrate to form two products without the use of water
d. To tell fibs
Answer:
c. To facilitate a reaction of one substrate to form two products without the use of water
Explanation:
A lyase is an enzyme that catalyzes - accelerates the chemical reaction - in which a substrate is broken into two molecules. The reaction does not involve hydrolysis or oxidation, so the water molecule is not included in the chemical reaction. Thus, the enzyme facilitates the reaction in which a molecule (substrate) is decomposed into two molecules with the elimination of chemical bonds.
Solid strontium chromate, SrCrO4, dissolves into its respective ions at 25°C. Suppose that in a particular solution, [Sr^2+]=6.0x10^-3M. Find the value of Ksp.
A) 3.6 x 10^-5
B) 6.0 x 10^-3
C) 3.6 x 10^-2
D) 7.7 x 10^-2
Answer:
A) 3.6 x 10^-5.
Explanation:
Hello there!
In this case, according to the given information, it turns out firstly necessary to write the equilibrium expression for the dissociation of strontium chromate:
[tex]Ksp=[Sr^{2+}][CrO_4^{2-}][/tex]
Thus, since strontium and chromate ions are in a 1:1 mole ratio, we can tell the concentration of both ions as the same; and therefore, the Ksp is:
[tex]Ksp=(6.0x10^{-3}M)(6.0x10^{-3}M)\\\\Ksp=3.6x10^{-5}[/tex]
Or option A) 3.6 x 10^-5.
Regards!
g An ionic bond involves ____ a. molecules that gain or lose an atom to develop a bonding charge b. molecules that bond together through a weak force c. atoms that either lose or gain an electron in order to bond d. atoms that share an electron to tightly bond
Answer:
a. molecules that gain or lose an atom to develop a bonding charge
Explanation:
Calculate the number of moles of magnesium, chlorine, and oxygen atoms in 7.40 moles of magnesium perchlorate, Mg(ClO4)2. Express the number of moles of Mg, Cl, and O atoms numerically, separated by commas.
Answer:
Number of moles Magnesium (Mg) = 7.40 moles
Number of moles Chlorine (Cl) = 14.8 moles
Number of moles of oxygen atoms = 29.6 moles
7.40;14.8;29.6
Explanation:
Step 1: Data given
Number of moles of magnesium perchlorate, Mg(ClO4)2 = 7.40 moles
Step 2: Calculate number of moles
In 1 mol of magnesium perchlorate, Mg(ClO4)2, we have:
1 Mol Magnesium (Mg)
2 moles of Chlorine (Cl)
8 moles of oxygen (O)
This means that for 1 mol of magnesium perchlorate, Mg(ClO4)2, we have the same amount of moles Magnesium (Mg), the double amount of moles of Chlorine (Cl) and 4x the amount of moles of oxygen (O)
Number of moles Magnesium (Mg)= 1 * 7.40 moles = 7.40 moles
Number of moles Chlorine (Cl) = 2 * 7.40 moles = 14.8 moles
Number of moles of oxygen atoms = 4 * 7.40 moles = 29.6 moles
7.40;14.8;29.6
1. Make ___________________
Observe an event. State only what we can
________ or ____________.
2. Ask ___________________
Ask a question that helps us find out _______ and _______ the event happened. We must be
able to answer the question with ________, or ________. We may need to __________ our question several times before it is__________.
3. Construct a_____________________
State the answer we think we’ll get when we ask
our question. This is called a
_________________. It’s based on our best
understanding of the event.
4. Test the hypothesis with an
_______________________
Test whether the hypothesis is ___________.
During the investigation, we collect _______ that
answers the testable question we asked.
Answer:
Explanation:
ANCHOR ANCHOR ANCHOR ANCHOR
The temperature of 10 kg of a substance rises by 55oC when heated. Calculate the temperature rise when 22 kg of the substance is heated with the same quantity of heat.
Answer:
The temperature rise is 25°C
Explanation:
The heat of a substance is obtained using the equation:
Q = m*S*ΔT
Where Q is heat in kJ, m is the mass of the susbtance, S is specific heat of the material and ΔT change in temperature.
Replacing:
Q/S = m*ΔT
As Q is constant because the heat is the same and S is the specific heat of the material (Constant). We can write:
m1*ΔT1 = m2*ΔT2
Where m is mass and ΔT change in temperature of 1, initial conditions of the substance and 2, final conditions of the substance.
Replacing:
m1 = 10kg
ΔT1 = 55°C
m2 = 22kg
ΔT2 = ?
10kg*55°C = 22kg*ΔT2
ΔT2 = 25°C
The temperature rise is 25°C
A 300 g sample of copper is heated to 285°C and then placed into 1000 g of water at 26.5°C period what was the final temperature of the water?
Answer:
33.4 °C
Explanation:
The final temperature of water will be the equilibrium temperature. This can be obtained as follow:
Mass of copper (M꜀) = 300 g
Initial temperature of copper (T꜀) = 285 °C
Specific heat capacity of copper (C꜀) = 0.385 J/gºC
Mass of water (Mᵥᵥ) = 1000 g
Initial temperature of water (Tᵥᵥ) = 26.5 °C
Specific heat capacity of water (Cᵥᵥ) = 4.184 J/gºC
Equilibrium temperature (Tₑ) =?
Heat lost by copper = Heat gained by water
M꜀C꜀(T꜀ – Tₑ) = MᵥᵥCᵥᵥ(Tₑ – Tᵥᵥ)
300 × 0.385 (285 – Tₑ) = 1000 × 4.184 (Tₑ – 26.5)
115.5(285 – Tₑ) = 4184(Tₑ – 26.5)
Clear the bracket
32917.5 – 115.5Tₑ = 4184Tₑ – 110876
Collect like terms
32917.5 + 110876 = 4184Tₑ + 115.5Tₑ
143793.5 = 4299.5Tₑ
Divide both side by 4299.5
Tₑ = 143793.5 / 4299.5
Tₑ = 33.4 °C
Therefore, the final temperature of water is 33.4 °C.
This kind of bond is formed when an atom with low electronegativity donates electrons to an
atom with high electronegativity.
Answer:
Ionic Bond
Explanation:
The atom with the higher electronegativity wants to fill its valence electron shell (meaning it wants 8 electrons in this shell). The atom with lower electronegativity will want to empty or donate an electron so that it can have an empty valence shell.
If a small amount of a strong base is added to buffer made up of a weak acid, HA, and the sodium salt of its conjugate base, NaA, the pH of the buffer solution does not change appreciably because:__________
a. the K, of HA is changed.
b. No reaction occurs.
c. the strong base reacts with A to give HA, which is a weak acid.
d. the strong base reacts with HA to give AOH and H'.
e. the strong base reacts with HA to give A, which is a weak base,
Answer:
e. the strong base reacts with HA to give A, which is a weak base
Explanation:
Let's consider a buffer made up of a weak acid, HA, and the sodium salt of its conjugate base, NaA. The function is a buffer system is to muffle the change in the pH when an acid or a base is added.
Let's suppose a strong base is added. Then, OH⁻ would be more available. OH⁻ ions react with the acid component of the buffer and its effect is reduced. The corresponding reaction is:
OH⁻ + HA ⇄ A⁻ + H₂O
As we can see, the strong base reacts with HA to give A, which is a weak base.
Which of the following will increase solubility the rate of the dissolving process of a gaseous solute in solvent? (mark all that apply) please help!
Answer: The increase in solubility or the rate of dissolving process of a gaseous solute in a liquid solvent is due to following:
Increasing agitationIncreasing temperatureIncreasing solute's partial pressure over the solventIncreasing solute's surface areaExplanation:
When agitation is increased then there will occur an increase in kinetic energy of the molecules of a substance. As a result, more number of collisions will take place due to which more amount of solute will dissolve into the solvent.
Similarly, increasing the temperature will further increase the kinetic energy of molecules. Hence, this will lead to more solubility of gaseous solute into the liquid solvent.
As solubility of a gas is directly proportional to the pressure of the gas above surface of the solution. So, an increase in solute's partial pressure over solvent will also lead to an increase in solubility of gaseous solute into liquid solvent.
When surface area of solute is increased then there will be more solute particles available for reaction. Hence, more collisions will take place. As a result, rate of reaction is more due to which there will be an increase in solubility.
Thus, we can conclude that the increase in solubility or the rate of dissolving process of a gaseous solute in a liquid solvent is due to following:
Increasing agitationIncreasing temperatureIncreasing solute's partial pressure over the solventIncreasing solute's surface areaIn what kind of orbitals do the lone-pair electrons on the singly bonded oxygen of methyl acetate reside, and are they in the same plane as the group
Answer:
Both lone pairs reside in sp3 orbitals; they are co-planar with the CH3 group.
Explanation:
In the compound, methyl acetate, the lone-pair of electrons on the singly bonded oxygen atom is accommodated in sp3 hybridized orbitals.
If we look at the compound, we will notice the both lone pair of electrons on oxygen are accommodated in sp3 orbitals which are co-planar with the CH3 group in the molecule.
Gold crystallizes in a face-centered cubic structure. What is the edge length of the unit cell if the atomic radius of gold is 144 pm?
407 pm
333 pm
204 pm
288 pm
Answer:
407 pm
Explanation:
For any elemental face-centered cubic structure, the relationship between the edge length of the unit cell and the atomic radius of its element is:
√2 * L = 4rWhere L is the edge length and r is the atomic radius.
With that in mind we can calculate the edge length:
√2 * L = 4 * 144 pmL = 407 pmA mixture of sodium hydroxide and strontium hydroxide contains a total of 0.19 moles of the two compounds. It requires 100.0 mL of 2.969 M HCl to neutralize all of the base. How many moles of sodium hydroxide were in the original mixture
Answer:
0.0831 moles of NaOH were in the original mixture
Explanation:
The strontium hydroxide, Sr(OH)2, requires 2 moles of HCl per mole of hydroxide to be neutralized.
The sodium hydroxide, NaOH, requires 1 mol of HCl per mol of hydroxide.
To solve this question we must write 2 equations:
(1) 0.19mol = X + Y
Where X = Moles NaOH; Y = Moles Sr(OH)2
The moles of HCl required are:
0.100L * (2.969mol / L) = 0.2969 moles HCl
0.2969 mol = X + 2Y(2)
Replacing (1) in (2):
0.19mol - Y = X
0.2969 mol = (0.19mol - Y) + 2Y
0.1069mol = Y
Moles X = Moles NaOH:
0.19mol = X + 0.1069mol
X = 0.0831 moles of NaOH were in the original mixture
Practice by predicting what would happen if the following underwent beta decay: (2
iv. Carbon -10 __________+ _____
v. Cesium-137 __________+ _____
vi. Thorium-234 __________+ _____
Answer:
See explanation and image attached
Explanation:
During beta emission, neutrons are converted into protons and electrons. The anti neutrino balances the spins.
When a nucleus undergoes beta emission, the mass number of the daughter nucleus produced in the process is the same as that of the parent nucleus but the atomic number of the daughter nucleus increases by one unit.
The product of the beta decay of the nuclides shown in the question is described in the image attached to this answer.
Someone plssss help meeee !!!! How much energy is required to vaporize 112 g of water? ???
Answer:
6.05 × 10⁴ cal
Explanation:
Step 1: Given and required data
Mass of water (m): 112 g
Enthalpy of vaporization of water (ΔHvap): 540 cal/g
Step 2: Calculate how much energy is required to vaporize 112 g of water
Vaporization is a physical change in which a substance goes from the liquid state to the gaseous state. We can calculate the energy required (Q) using the following expression.
Q = ΔHvap × m
Q = 540 cal/g × 112 g = 6.05 × 10⁴ cal