Answer:
b calcium
Explanation:
Given:
CH4 + 2O2 → CO2 + 2H2O, ΔH = -890 kJ/mol
How much energy is released when 59.7 grams of methane (CH4) reacts with oxygen?
The combustion of 59.7 grams of methane releases ____ kilojoules of energy
Answer:
The combustion of 59.7 grams of methane releases 3320.81 kilojoules of energy
Explanation:
Given;
CH₄ + 2O₂ → CO₂ + 2H₂O, ΔH = -890 kJ/mol
From the combustion reaction above, it can be observed that;
1 mole of methane (CH₄) released 890 kilojoules of energy.
Now, we convert 59.7 grams of methane to moles
CH₄ = 12 + (1x4) = 16 g/mol
59.7 g of CH₄ [tex]= \frac{59.7}{16} = 3.73125 \ moles[/tex]
1 mole of methane (CH₄) released 890 kilojoules of energy
3.73125 moles of methane (CH₄) will release ?
= 3.73125 moles x -890 kJ/mol
= -3320.81 kJ
Therefore, the combustion of 59.7 grams of methane releases 3320.81 kilojoules of energy
Answer:
The combustion will release -3,321 KJ/mol of energy
Explanation:
water is a highly polar molecule with strong hydrogen bonding. one of the results of this is that water can climb up a narrow tube. the phenomenom is known as:
A. catapult action (aka trebuchet onfire)
B. capillary action
C. carpel tunnel syndrom
D. capitalization
Answer:
Option B, Capillary action
Explanation:
Water molecules attach with the molecules of the surface of the container in which they are kept. This is because of the cohesive force within the molecules of water and adhesive force between the molecules of water and other substances.
The water rises up in a capillary tube because of water molecules adhere at the edges thereby creating a meniscus in the upside turned direction. The surface is kept intact by the surface tension
Now capillary action specifically occurs when adhesion to the surface of the container is higher than the cohesion between the water molecules.
Hence, option B is correct
(Multiple Choice, 30 pts)
A student thinks that halogens are highly reactive because their electrons are weakly attracted to their nuclei. Which is evidence that disputes this student's idea?
A. Halogens react with alkali metals.
B. Halogens cannot react with noble gases.
C. Halogens tend to attract electrons when bonding.
D. Halogens have a full octet of electrons.
Answer:
c
Explanation:
¨Halogens being non metals have greater electronegativities hence, attract electrons and making the statement disputed. Nobel gases are highly stable; this explains why they are nonreactive. They do not form chemical bonds because they only have a little tendency to either gain or lose an electron; on the other hand, halogens are reactive because they only need one additional electron to complete their octet. ¨
i found that from another users answer for the same question
Answer:
answer c
Explanation:
Na2O+H2O= 2NaOH how many grams of Na2O are required to produce 1.06*10^2 grams of NaOH
Answer:
77.5 grams of Na2O
Explanation:
Convert grams to mols.
1.06 x 10^2 grams x 1 mol NaOH/39.99
= 2.50 mols NaOH
Find the mole ratio of NaOH and Na2O
1:2
Convert mols NaOH to Na2O mols
2.50 mols NaOH x 1 mol Na2O/2 mols NaOH
= 1.25 mols Na2O
Convert to grams
1.25 mols Na2O x 61.98 grams Na2O/1 mol
= 77.5 grams Na2O required to produce 1.06 x 10^2 grams of NaOH
On May 3, Zirbal Corporation purchased 4,500 shares of its own stock for $36,000 cash. On November 4, Zirbal reissued 800 shares of this treasury stock for $7,200. Prepare the May 3 and November 4 journal entries to record Zirbal's purchase and reissuance of treasury stock.
Answer:
Explanation:
Each share costs $36000/4500
= $8
800 shares will cost 800*8
= $6400
Find attached the journal
Which statement describes how a basic coffee cup calorimeter works?
OOO
It measures the mass of a substance given the specific heat and temperature of water in a cup of known size.
It measures the density of a substance given the mass, specific heat, and temperature of water in a cup of known size,
It uses the mass and specific heat of water along with a pressure gauge to measure the gain or loss of energy when a substance is
added.
It uses the mass and specific heat of water along with a thermometer to measure the gain or loss of energy when a substance is
added.
Answer:
It uses the mass and specific heat of water along with a thermometer to measure the gain or loss of energy when a substance is added.
Explanation:
The calorimeter is an instrumental device, which is used to measure the heat of chemical reactions. The heat is measured when the reactants change their state in specified conditions.
The correct answer is:
Option D. It uses the mass and specific heat of water along with a thermometer to measure the gain or loss of energy when a substance is added.
The coffee cup calorimeter works as:
1. Coffee cup is a type of insulator. The cup of styrofoam with an inserted thermometer can calculate the heat transfer.
2. The thermometer is used to measure the change in the enthalpy of the reaction.
3. The water in the cup absorbs the heat from a reaction, and the cup is adiabatic. Thus, the outer cup is an insulator.
4. The coffee cup measures the specific heat and mass of the water during a chemical change.
Thus, the coffee cup calorimeter uses the heat transfer and mass of the water when a substance is added.
To know more about calorimeter, refer to the following link:
https://brainly.com/question/10987564
If O2(g) reacts with H2(g) to produce H2O, what is the volume of H2O obtained from 1 L of O2?
Hint: Write a balanced equation first!
Answer:
2L
Explanation:
We'll begin by writing the balanced equation for the reaction this is illustrated below:
2H2 + O2 —> 2H2O
1 mole of a gas occupy 22.4L.
1 mole of O2 occupy 22.4L.
2 moles of H2O occupy = 2 x 22.4 = 44.8L.
From the balanced equation above,
22.4L of O2 produced 44.8L of H2O.
Therefore, 1L of O2 will produce = 44.8/22.4 = 2L.
Therefore, 1L of O2 will produce 2L of H2O.
Which of the following Noble Gases has a mass of 10.0 g?
Answer:
Option B is correct.
0.119 mole of Kr has a mass of 10.0 g
Explanation:
The complete Question was ontained online, albeit, it was incomplete, even from the online source. But the solution is possible based on the part of the question obtained.
Complete Question
Which of the following Noble Gases has a mass of 10.0 g?
A. 2.02 mol Ne B. 0.119 mol Kr C.
Solution
Number of moles = (Mass)/(Molar Mass)
Mass = (Number of moles) × (Molar mass)
Checking the options, one at a time,
A. 2.02 moles of Neon
Number of moles = 2.02 moles
Molar Mass of Neon = 20.1797 g/mol
Mass = 2.02 × 20.1797 = 40.762994 g ≠ 10.0 g
Not the answer.
B. 0.119 moles of Krypton
Number of moles = 0.119 moles
Molar Mass of Krypton = 83.798 g/mol
Mass = 0.119 × 83.798 = 9.971962 g ≈ 10.0 g
This is definitely the answer.
Hope this Helps!!!
Answer: 0.119 mol Kr
Explanation:
The Ka of acetic acid (CH3COOH) is 1.8 x10-5.
Calculate the pH of a 3.0 M solution of acetic acid.
Answer: 2.13
Explanation: i crawled so you could run :)
Which characteristic most likely describes the water in Lake Taal?
Select the correct answer.
o The water will appear slightly red.
O The water will have a slippery feel.
The water will taste bitter.
The water will taste sour.
Answer: The water will taste sour.
Explanation:
Answer: D. The water will taste sour (Edmentum)
Explanation:
What is the concentration of a solution in which 10.0 g of AgNO, is dissolved in 450 mL of solution?
M
Answer:
M=0.15
Explanation:
138 g AgNO -> 1 mol AgNO
10 g AgNO -> x
x= (10 g AgNO * 1 mol AgNO)/138 g x=0.07 mol AgNO
450 mL=0.45 L
M= mol solute/L solution
M= 0.07 mol AgNO/0.45L
M=0.15
According to one acid-base theory a molecule acts as an acid when the molecule
A group of tissues working together is?
Answer:
An organ
Explanation:
An organ is one or more tissues that work together to form a specific function.
- Hope that helps! Please let me know if you need further explanation.
Wax is a nonpolar substance . In which type of substance is it the most soluble ?
Answer:
nonpolar
Explanation:
Use the phrase "like dissolves like"
- Hope that helps! Please let me know if you need further explanation.
A sample of diborane gas has a pressure of 345 torr at a temperature of -15c and volume of 3.48L if conditions are changed so that the temperature is 36c and the pressure is 468 torr what will be the volume of the sample
Answer: 3.05L= V2
Explanation:
using
P1V1/T1=P2V2/T2
where p1= 345torr
T1, tempertaure= -15c+ 273=258K
T2, temperature= 36+ 273=309K
p2, Pressure= 468 torr
V2=???
P1V1/T1=P2V2/T2
v2=P1V1T2/T1P2= 345X3.46L X 309/ 258X 468=
V2= 3.05L
Particles of the substance have the most kinetic energy when the substance is(a)_______. The part of the graph that represents where the substance has the least amount of potential energy is labeled(b)_______.
multiple choice answers available.
(a)
1. A gas
2. A solid
3. Melting
4. vaporizing
(b)
1. Solid
2. Vaporizing
3. melting
4.liquid
5.gas
Answer: 1- gas 2- solid
Explanation:
I need help. Please give a detailed answer:
Hydrogen cyanide (HCN) is a colorless gas. It is poisonous and smells like almonds. Draw a Lewis structure for this compound, explain why you drew the Lewis structure the way that you did, and predict the shape of the molecule.
Answer:
What ever you want. I made it like this because it would make the most logical sense with a mix of the Dot system.
Explanation:
Since the question says to explain yourself, and to predict, really any answer would be correct since it sounds like it's not asking for a correct answer, but more of an answer that would make sense to you and explain it. That's really what chemistry is, a bunch of educated responses and guesses with confidence.
How many copper atoms are in a 70g copper
Answer:
[tex]x = 6.634\times 10^{23}\,atoms[/tex]
Explanation:
The quantity of atoms within the mass of copper is determined by multiplying the quantity of moles by the Avogadro's Number:
[tex]x = \left(\frac{70\,g}{63.546\,\frac{g}{mol}} \right)\cdot \left(6.022\times 10^{23}\,\frac{atoms}{mol} \right)[/tex]
[tex]x = 6.634\times 10^{23}\,atoms[/tex]
Answer:
6.64x10^23 atoms.
Explanation:
From Avogadro's hypothesis, 1 mole of any substance contains 6.02x10^23 atoms. This implies that 1 mole of Cu also contains 6.02x10^23 atoms.
1 mole of Cu = 63.5g
If 63.5g of Cu contains 6.02x10^23 atoms,
Then 70g of Cu will contain = (70x6.02x10^23) /63.5 = 6.64x10^23 atoms.
Therefore, there are 6.64x10^23 atoms in 70g oh Cu
Which phrase describes a volcano that is not expected to erupt again?
quiet volcano
extinct volcano
dormant volcano
explosive volcano
5. On what organ does alcohol have the most noticeable effect?
Answer:
the liver
Explanation:
it processes alcohol, work very hard
Gas Laws
Assignment Active
Applying Gas Laws to Aerosol Can D
(国座
Explain why it is not a good idea to throw an
aerosol can into a fire. Which gas law applies?
DONE
Answer:
Ideal Gas Law
PV = nRT
Explanation:
Pressure is proportional to temperature;
The heat of the fire would cause increased pressure inside the closed aerosol vessel, eventually resulting in explosion of the vessel, once the temperature rises enough.
Which statement describes a gas condensing into a liquid?
A.
The atoms in the molecules get heavier so they move less.
B.
The molecules break into smaller pieces that take up less space.
C.
The molecules stick together to make bigger molecules.
D.
The molecules get closer together and move more slowly.
Answer: molecules get closer
Explanation:
Condensation is the process in which molecules of a gas slow down, come together, and form a liquid. When gas molecules transfer their energy to something cooler, they slow down and their attractions cause them to bond to become a liquid
hope this helps
pls mark me brainliest
Answer:
D. The molecules get closer together and move more slowly.
Calculate the hyrdrogen ion concentration [h+] for the aquesous solution in which [oh-] is 1 x 10-2 mol/l.Is the solution acidic,basic,or neutral? Show your work
Answer:
- [tex][H^+]=1x10^{-12}[/tex]
- Basic.
Explanation:
Hello,
In this case, given the concentration of hydroxyl ions, one could compute the pOH as shown below:
[tex]pOH=-log([OH^-])=pOH=-log(1x10^{-2})=2[/tex]
Then, since the pOH and the pH are related by:
[tex]pH+pOH=14[/tex]
One computes the pH:
[tex]pH=14-pOH=14-2=12[/tex]
Now, we compute the concentration of hydronium by:
[tex][H^+]=10^{-pH}=10^{-12}[/tex]
[tex][H^+]=1x10^{-12}[/tex]
Finally, since the pH is greater than 7 (neutral point) we conclude that the solution is basic.
Best regards.
Answer:
A. Hydrogen ion concentration, [H+] is 1x10^–12 mol/L
B. Since the pH is 12, the solution is basic.
Explanation:
Data obtained from the question. This includes the following:
Concentration of Hydroxide ion, [OH-] = 1x10^–2 mol/L
Concentration of Hydrogen ion, [H+] =.?
pH =..?
A. Determination of the hydrogen ion concentration, [H+] .
The hydrogen ion concentration, [H+] can be obtained as follow:
[H+] x [OH-] = 1x10^–14
[OH-] = 1x10^–2
[H+] x 1x10^–2 = 1x10^–14
Divide both side by 1x10^–2
[H+] = 1x10^–14 / 1x10^–2
[H+] = 1x10^–12 mol/L
B. Determination of the pH of the solution.
The pH of the solution can be obtained as follow:
pH = –Log [H+]
[H+] = 1x10^–12 mol/L
pH = –Log 1x10^–12
pH = 12.
Then pH of a solution ranges between 0 and 14.
A pH reading between 0 and 6 is termed an acidic solution, a pH reading of 7 is termed a neutral solution and a pH reading between 8 and 14 indicates an alkaline or a basic solution.
The higher the pH value, the more alkaline or basic the solution becomes.
Since the pH is 12, the solution is basic.
Why might you have difficulty determining the pH of bleach using ph strips?
Answer:
pH test strips will lose colour and their pH sensitivity as strips are made from universal indicator. Universal indicator is composed of phenolphthalein, methyl red, methyl orange and thymol blue.
Explanation:
pH test strips are made from the universal indicator. The universal indicator is composed of phenolphthalein, methyl red, methyl orange, and thymol blue. All of these will react with chlorine in bleach. As a result, they will lose color and pH sensitivity. Due to this, it is difficult to determine the pH of bleach using ph strips.
Calculate the pressure using the formula P=1.03+ mass on syringe/area of top of syringe
Answer:1.08
Explanation:
Answer:
1.08kg/cm^2
Explanation:
Edge2021
ionic compounds conduct electricity in the solid state true or false
In solid form, ionic compounds do not conduct electricity. Ionic compounds will conduct electricity when melted to their liquid state. This is due to the electrons being locked in place when in solid form, but liquid form allows for the electrons to move freely.
What are the four main parts of the Sun? *
Answer: The inner layers are core, radiative zone, and convective zone. The putter layers a photosphere, the chromosphere, the transition region and the corona
Give the molecular geometry and number of electron groups for sf4. give the molecular geometry and number of electron groups for . square planar, 6 electron groups square pyramidal, 6 electron groups t-shaped, 5 electron groups octahedral, 6 electron groups seesaw, 5 electron groups
Answer:
5 electron groups, see saw
Explanation:
During the formation of SF4, the sulfur atom usually bonds with each of four fluorine atoms where 8 of valence electrons are used. The four fluorine atoms have 3 lone pairs of electrons in its octet which will further utilize 24 valence electrons. In addition, two electrons are present as a lone pair on the sulfur atom. We can determine sulfur’s hybridization state by counting of the number of regions of electron density on sulphur (the central atom in the molecule). When bonding takes place there is a formation of 4 single bonds to sulfur and it has 1 lone pair. Looking at this, we can say that the number of regions of electron density is 5. The hybridization state is sp3d.
SF4 molecular geometry is seesaw with one pair of valence electrons. The molecule is polar. The equatorial fluorine atoms have 102° bond angles instead of the actual 120° angle. The axial fluorine atom angle is 173° instead of the actual 180° bond angle.
How do astronomers know about the future collision of Andromeda and the Milky Way?
A) All galaxies will collide at some point
B) The two galaxies have collided previously
C) Astronomers have observed their movements over time
D) The Milky Way has changed course to head toward Andromeda
Answer:
Astronomers have observed their movements over time
Explanation:
Just took the test!!!
The future collision of Andromeda and milky way are known by astronomers because ; ( C ) Astronomers have observed their movements over time
Andromeda also known as messier 31 is a spiral galaxy that appears as a milky blur when viewed from the earth and it is believed to be slightly over 2.5 million years old.
Astronomers predict that based on its movement and the movement of the Milky way there is most likely going to be a collision in future between the Andromeda and milky way.
Hence we can conclude that The future collision of Andromeda and milky way are known by astronomers because Astronomers have observed their movements over time
Learn more : https://brainly.com/question/2849133
Which statements describe gridlines on a map? Select three options. They are measured in degrees. They set up a reference system. They make straight lines on a globe. They run north to west and south to east. They divide Earth into four equal parts.
Answer:
The options that apply to the description of grid-lines of the map are;
They are measured in degrees
They set up a reference system
They divide Earth into four equal parts
FIRST OPTION , SECOND OPTION and FIFTH OPTION are correct.
Explanation:
FIRST OPTION gave the describtion that the grid-lines of the map are measure in degrees,this option is applied to the gridlines on a map because the grid are lined as a result of angular measurement which makes it to makes the unit to be measured degrees and angles.
SECOND OPTION described it as been set up by a reference system which let us know that the area that are plotted were all grid as a result of the size
FIFTH OPTION also applied to the
description of the gridlines on a map because the Earth is divided into 4 equal parts through the Prime Meridian i.e the latitudinal line and longitudinal line .
.
Answer:
They are measured in degrees.
They set up a reference system.
They divide Earth into four equal parts.
Explanation:
i took the test
