Answers
Answer:
–4020 KJ
Explanation:
The following data were obtained from the question:
H₂(g) + F₂(g) —> 2HF(g) ΔH = –536 KJ
Next, we shall determine the mass of H₂ that reacted from the balanced equation to produce –536 KJ of heat energy. This can be obtained as follow:
Molar mass of H₂ = 2 × 1 = 2 g/mol
Mass of H₂ from the balanced equation = 1 × 2 = 2 g.
Summary:
From the balanced equation above,
2 g of H₂ reacted to produce –536 KJ of heat energy.
Finally, we shall determine the heat change produced by the reaction of 15 g of H₂. This can be obtained as follow:
From the balanced equation above,
2 g of H₂ reacted to produce –536 KJ of heat energy.
Therefore, 15 g of H₂ will react to produce = (15 × –536)/2 = –4020 KJ of heat energy.
Thus, the heat change for the reaction is –4020 KJ
Related Questions
How many oxygen atoms are contained in a sample of aluminum nitrate, Al(NO3)3, with a
mass of 4.285 x 10-21 g? (molar mass of Al(NO3)3 is 213 g mol-l)
a 109
b. 54
c. 9
d. 3
Answers
the answer is 9
Explanation:
Explanation: In 1 formula unit of Al(NO3)3 , there are (clearly!) 9 atoms of oxygen, 3 nitrogen atoms, and 1 aluminum atom.
14. A researcher Is curious to find out what effect classical music has on people's level of relaxation
(as measured by heart rate). She suspects that listening to classical music will make people feel
more calm and relaxed. The researcher lets one group listen to classical music for one hour and
then do a relaxing activity, like reading or drawing for another hour. She lets the other group sit in a
qulet room for two hours (they hear no music). After two hours, she monitors the heart rate of each
participant to measure their level of relaxation.
What is the error in thls experiment design?
A. There are two independent variables: classical music and an additional relaxing activity
B. There are two independent variables: the amount of time and heart rates
C. There are two dependent variables: classical music and an additional relaxing activity
D. There are two dependent variables: the amount of time and heart rates
Answers
Answer:
It should be "B"
Explanation:
:) :) :) :) :) :)
RODINNIS
COURSES
onal Science
Attempt 1 of 2
Which of the following distinctions are used to identify sedimentary rock? Select all that apply.
o where is was formed
conditions it was formed under
n when it was formed
what it is composed of
how many layers it consists of
NEED HELP ASAP (check the picture)
Answers
where it was formed and. conditions it was formed under
What number of cations is present in 1.17g of sodium chloride ?
Answers
Answer:
1.2 × 10^22 atoms.
Explanation:
Firstly, cations refers to the positively charged atom in the ionic compound, which is Na+.
Given the mass of NaCl as 1.17g, the number of moles of NaCl can be calculated this:
Molar mass of NaCl = 23 + 35.5
= 58.5g/mol
Mole = mass/molar mass
Mole = 1.17/58.5
Mole = 0.02moles
Using Avagadro's number, 6.022 × 10^23 atoms of Na+ are in 1 mole of NaCl.
In 0.02 moles of NaCl, there are 0.02 × 6.022 × 10^23 of Na+
0.1204 × 10^23 atoms
1.2 × 10^22 atoms of Na+ (cation)
Describe the brightness and temperature of the stars classified as giants.
Answers
Answer:
A hotter star should be brighter than a cooler star. ... Although they are cool [red], they are very luminous, and therefore bright. In the Main Sequence, stars that are cool are not as luminous. Because the energy is spread across a larger area, surface temperatures are actually cooler, reaching only 2,200 to 3,200 degrees Celsius (4,000 to 5,800 degrees Fahrenheit), a little over half as hot as the sun
Explanation:
1. How many molecules of H,O are in 4.32 moles?
Answers
Answer:
dont know
Explanation:
18. Which statement about photosynthesis is FALSE?
a
Tilmy green pigment chlorophyll captures light
energy
b Oxygen is needed as a reactant to produce
glucose
The process converts light energy from the
csun into chemical energy in the bonds of
glucose.
d
Carbon dioxide is needed as a reactant to
produce glucose.
Answers
Which statement about photosynthesis is FALSE?
Answer:
b. Oxygen is needed as a reactant to produce
glucose is the incorrect statement here
Explanation:
plants uses simple raw materials to prepare their food , which includes water ( H2O ) and Carbon dioxide ( CO2 ).
and traps sunlight by Green pigments known as chlorophyll and stores these energy in bonds of glucose molecules
so ,
after this reaction glucose and oxygen is formed as products
● hence we conclude that Oxygen is not needed as a reactant to produce glucose , oxygen is the bi product formed during photosynthesis.
What is an ion? What are the different properties of an ion? There is more than one answer choose all that apply
Answers
Answer:
An ion is an atom or molecule that has a different number of electrons than protons, so it has a charge.
Explanation:
Trust me please
What is the difference between condensation and evaporation?
Answers
Condensation is the phase change from gas to a liquid, whereas evaporation is the phase change from liquid to gas.
What is the atomic number of an element that has seven protons and eight neutrons and seven electrons?
Answers
Answer:
Nitrogen has an atomic number of 7 (Z=7) because it has 7 protons in its nucleus. Some nitrogen atoms have an atomic mass number of 15 (A=15). A is the number of neutrons plus protons in the nucleus. However, we already know that there are 7 protons
Answer:
Atomic number = Number of protons = Number of electrons
Atomic number = 7
Which of the following was NOT among Democritus's ideas?
A. Matter consists of tiny particles called atoms.
B. Atoms are indivisible.
C. Atoms retain their identity in a chemical reaction.
D. Atoms are indestructible.
Answers
Answer:
pretty sure its C
Explanation:
Democritus was all about the consept f tiny indestructible partivls called atoms so C is the only one that doesn' t fit
Answer:
I'm pretty sure it's A
In Step 5, you will calculate H+/OH– ratios for more extreme pH solutions. Find the concentration of H+ ions to OH– ions listed in Table B of your Student Guide for a solution at a pH = 2. Then divide the H+ concentration by the OH– concentration. Record these concentrations and ratio in Table C. What is the concentration of H+ ions at a pH = 2? mol/L What is the concentration of OH– ions at a pH = 2? mol/L What is the ratio of H+ ions to OH– ions at a pH = 2? : 1
Answers
The ratio of H⁺ ions to OH⁻ ions at a pH = 2 is 10¹⁰
Further explanationGiven
ph = 2
Required
The concentration of H⁺ and OH⁻ ions
Solution
The concentration of H⁺ ionspH=-log[H⁺]
2=-log[H⁺]
[H⁺]=10⁻²
The concentration of OH⁻ ionspH+pOH=14
pOH=14-2
pOH=12
pOH=-log[OH⁻]
12=-log[OH⁻]
[OH⁻]=10⁻¹²
The ratio of H⁺ ions to OH⁻ ions at a pH = 2[tex]\tt \dfrac{10^{-2}}{10^{-12}}=10^{10}[/tex]
Answer:
First one: 0.01
second one: 0.000000000001
third one: 10000000000
Structural formula of 2 ethyl, 4 methyl-Heptane
Answers
Hey this answer question
4. Pb +FeSO, - PbSO, +Fe
Reaction Type:
Answers
Answer:Fe
Explanation:
I need the answer for number 17 pls
Answers
Can anybody help me asap pls
Answers
Answer:
Here is ur answer...
Explanation:
2) Half-filled d orbital increases the stability of the element.
Which term refers to the simplest form of matter that cannot be broken down chemically?
A.Element
B.compound
C.Mixture
D.solution
Answers
Answer:
I believe the answer is A, an Element.
Explanation:
It's a substance that cannot be broken down into simpler substances. If I'm wrong, let me know!
All of the following rivers are labeled on the map above except the __________ River.
A. Danube
B. Volga
C. Lena
D. Ob
Answers
What is this equation balanced?
Answers
Answer:
2Al + 6HCl —> 3H₂ + 2AlCl₃
Explanation:
From the question given above:
Al + HCl —> H₂ + AlCl₃
The above equation can be balance as illustrated below:
Al + HCl —> H₂ + AlCl₃
We have 1 atom of Cl on the left side and 3 atoms on the right side. It can be balance by putting 6 in front of HCl and 2 in front of AlCl₃ as shown below:
Al + 6HCl —> H₂ + 2AlCl₃
We have 6 atoms of H on the left side and 2 atoms on the right side. It can be balance by 3 in front of H₂ as shown below:
Al + 6HCl —> 3H₂ + 2AlCl₃
We have 1 atom of Al on the left side and 2 atoms on the right side. It can be balance by putting 2 in front of Al as shown below:
2Al + 6HCl —> 3H₂ + 2AlCl₃
Thus, the equation is balanced.
What can be concluded from the statements above?
A. A harmful compound can become harmless when its elements are separated.
B. A harmless compound can become harmful when its elements are separated.
C. Breaking a compound into its separate elements has no noticeable effects.
D.Breaking a compound into its separate elements can create carbon dioxide.
Answers
Answer:
B
Explanation:
I am not sure why
Answer:
Yea I think B as well!!!!!
how many total elements are in marble?
Answers
Answer:There are total 118 elements in world as about marbale
Explanation:
why does human cells perform more functions
Answers
Answer:
Human cells are eukaryotic which means they are more complicated, bacteria cells are prokaryotic which means they are simpler and viruses are not even cells at all, they are just genetic material in a protein shell. Not all bacteria make us sick, most actually help us have emunity to the virus. Hope this helps
Explanation:
Answer:
Cells are the basic building blocks of all living things. The human body is composed of trillions of cells. They provide structure for the body, take in nutrients from food, convert those nutrients into energy, and carry out specialized functions. Cells have many parts, each with a different function.
Explanation:
I Wanted to ask.. it's a weird question I know or maybe it's gonna get reported But
Why is my friend so irritating..
Answers
Answer:
if hyper its probaly because the have ADHD which is a type of drug that helps people with behavior disorders . the might have ticks wich is something that people can not control.
Explanation:
In Step 5, you will calculate H+/OH– ratios for more extreme pH solutions. Find the concentration of H+ ions to OH– ions listed in Table B of your Student Guide for a solution at a pH = 2. Then divide the H+ concentration by the OH– concentration. Record these concentrations and ratio in Table C. What is the concentration of H+ ions at a pH = 2? mol/L What is the concentration of OH– ions at a pH = 2? mol/L What is the ratio of H+ ions to OH– ions at a pH = 2? : 1
Answers
Answer:0.01
0.000000000001
10,000,000,000
Explanation:
Answer:
1. What is the concentration of H+ ions at a pH = 2?
0.01 mol/L
2. What is the concentration of OH– ions at a pH = 2?
0.000000000001 mol/L
3. What is the ratio of H+ ions to OH– ions at a pH = 2?
10,000,000,000 : 1
Have a wonderful day/night! :)
ANSWER ASAP Which part of the picture shows evidence of matter scattering light waves in
many different directions?
O A. The color of the tree appears black against the sky.
O B. The image of the moon in the sky is incomplete.
OC. The image of the moon on the water's surface is distorted.
OD. The colors on the water's surface match the colors in the sky.
Answers
Answer:
The evidence of matter scattering light wave in many different directions is;
D. The colors on the water's surface match the colors in the sky
Explanation:
Light scattering is used to describe the sending of a given beam of light in many directions (by tiny particles) when the light passes through a medium, due to the disruption of the bath of the light ray as it bumps into the tiny particles
Water has the nature of absorbing the red light. The light that enters the water is scattered by the tiny particles in the water such that the blue light which is the spectrum of light water allows to pass through is reflected along with the reflection of the sky and the colors of the water surface match the colors of the sky.
Answer:
C.
Explanation:
I took the quiz
Explain five physical and/or chemical properties that you need to consider for the substances before using them as construction materials for buildings
Answers
Answer: There are many properties of a metal which is taken into consideration when it is used for construction
Explanation:
The properties can be physical, chemical, et cetera. The physical properties that is considered are:
1. Durability: It can be defined as the property of the material to withstand the atmospheric pressure and other factors.
2. Density: The ratio of mass by volume of a material (homogeneous material) is called as density.
3. Fire resistance: The ability of the material to withstand in fire without changing its size or shape.
4. Weather resistance: The ability of the material to withstand the weather which could be variable round the year.
5.Water absorption: The ability of the material to absorb water and retain it.
PLEASE HELP! SEE ATTACHED!
Answers
Answer:
Ans => C => 43.3%
Explanation:
2CO + O₂ => 2CO₂
Given 1g CO = 1g/28g·mol⁻¹ = 0.036 mol CO
b/c coefficient of CO = coefficient of CO₂ => moles CO₂ = 0.036 mol = 0.036mol x 44g/mol = 1.57 gCO₂ (theoretical yield)
%Yield = (actual yield/theoretical yield) x 100% = (0.68g/1.57g) x 100% = 43.3%
What is one abiotic factor that all biotic factors need to survive??
Answers
Answer:
there r mainly three abiotic factors where all biotic factors need to thrust and survive,
They're i) Air
ii) Water
iii) Land
Answer:Water
Explanation:
what is the anwser to this question
Answers
Answer:
N/A
Explanation:
"what is the anwser to this question" Is Not Available because this no question.
Please like this.
How many grams are in 657 L of N2 gas at STP?
Answers
Answer:
821.25gm
Explanation:
volume = 657
no of mole = 657/22.4
mass = no of mole * molecular mass
mass = 657/22.4*28
= 821.25gm
