Answer:
Balancing an equation
Explanation:
These steps describes the processes which are involved in balancing a chemical equation.
In balancing the a chemical equation, the law of conservation of mass is strictly adhered to. It suggests that in a chemical reaction, atoms are neither created nor destroyed, but they combine with one another.
Therefore, the number atoms at start and end of a reaction must be the same. You can use coefficients to increase the atoms on each side. Also, check to makes sure the number of atoms on both sides are the same. Count the atoms on each side of the expression.Answer:
balancing
Explanation:
When a student dissolves 2.50 g of LiCl in 100.0 mL of water (100.0 g) the temperature rises from 24.0 oC to 29.11oC. What is ∆H in KJ/mol for the dissolution of LiCl in water? Make sure you include the correct sign for ∆H and units (with a space between number and unit)
Answer:
[tex]36.273\ \text{kJ/mol}[/tex]
Explanation:
m = Mass of LiCl = 2.5 g
M = Molar mass of LiCl = 42.394 g/mol
c = Specific heat of water = [tex]4.186\ \text{J/g}^{\circ}\text{C}[/tex]
[tex]\Delta T[/tex] = Change in temperature = [tex]29.11-24=5.11\ ^{\circ}\text{C}[/tex]
[tex]m_w[/tex] = Mass of water = [tex]\rho V=1\times 100=100\ \text{g}[/tex]
Number of moles
[tex]n=\dfrac{m}{M}\\\Rightarrow n=\dfrac{2.5}{42.394}\\\Rightarrow n=0.05897\ \text{mol}[/tex]
Heat is given by
[tex]Q=m_wc\Delta T\\\Rightarrow Q=100\times 4.186\times 5.11\\\Rightarrow Q=2139.046\ \text{J}[/tex]
Enthalpy is given by
[tex]\Delta H=\dfrac{Q}{n}\\\Rightarrow \Delta H=\dfrac{2139.046}{0.05897}\\\Rightarrow \Delta H=36273.46\ \text{J/mol}=36.273\ \text{kJ/mol}[/tex]
The enthalpy for the dissolution is [tex]36.273\ \text{kJ/mol}[/tex].
If I dilute 250 mL of 0.10 M lithium acetate solution to a volume of 750 mL,
what will the concentration of this solution be?
Answer:
0.033 M
Explanation:
From the question given above, the following data were obtained:
Volume of stock solution (V1) = 250 mL
Molarity of stock solution (M1 ) = 0.10 M
Volume of diluted solution (V2) = 750 mL
Molarity of diluted solution (M2) =.?
Thus, we can obtain the molarity of the diluted solution by using the dilution formula as illustrated below:
M1V1 = M2V2
0.1 × 250 = M2 × 750
25 = M2 × 750
Divide both side by 750
M2 = 25/750
M2 = 0.033 M
Therefore, the molarity of the diluted solution is 0.033 M.
1. When a mechanical wave, such as sound, reflects off a surface, what can the
reflected wave tell you about the surface?
An echo or a reverberation can result from the reflection of sound waves off physical surfaces. Small rooms with dimensions of 17 meters or fewer, breadth, and length frequently experience reverberation.
What is reflection ?When two different media come together at an interface, a wavefront might change direction so that it returns to the first medium, which is known as reflection. The reflection of light, sound, and water waves are typical examples.
According to the law of reflection, the angle of incidence and angle of reflection are equal. The reflected wave will typically be inverted for mechanical waves traveling from a less dense medium into a more dense medium.
A portion of a wave will often bounce back into the original medium when it encounters the interface between two different media. We call this process "reflection." Optical reflection in mirrors, where light waves reflect off a smooth surface, is a well-known example of reflection.
Thus, An echo or a reverberation can result from the reflection of sound waves off physical surfaces.
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Which equation shows how to calculate how many grams (g) of KOH would
be needed to fully react with 4 mol Mg(OH)2? The balanced reaction is:
MgCl2 + 2KOH → Mg(OH)2 + 2KCI
Answer:
A.
General Formulas and Concepts:
Chemistry - Stoichiometry
Using Dimensional AnalysisExplanation:
Step 1: Define
Given: 4 mol Mg(OH)₂
RxN: MgCl₂ + 2KOH → Mg(OH)₂ + 2KCl
Step 2: Identify Conversions
Molar Mass of K - 39.10 g/mol
Molar mass of O - 16.00 g/mol
Molar mass of H - 1.01 g/mol
Molar Mass of KOH - 39.10 + 16.00 + 1.01 = 56.11 g/mol
Step 3: Stoichiometry
[tex]4 \ mol \ Mg(OH)_2(\frac{2 \ mol \ KOH}{1 \ mol \ Mg(OH)_2} )(\frac{56.11 \ g \ KOH}{1 \ mol \ KOH} )[/tex]
Answer:
check the attachment/picture below!
Explanation:
I had just taken that quiz! :D
i dont understand this i cant think :These ions have the same stable electron configuration as the noble gas helium. All Group 1 atoms can lose one electron to form positively charged ions. ... Elements in Groups 15,16 and 17, find it easier to gain electrons than lose them.
Answer:
Li atoms readily give up one electron to form positively charged, Li+ ions. These ions have the same stable electron configuration as the noble gas helium. All Group 1 atoms can lose one electron to form positively charged ions.
Explanation:
I DON'T KNOW IF THIS IS THE RIGHT ANSWER BUT I'M TRYING TO JUST ANSWER.
Answer:
Explanation:
-We know that an atom is table if they have 8 valence electrons (like noble gases, they are stable)
-Group 1 atoms only has 1 valence electron, in order to become stable, they are desperately wanted to lose that one valence electron to become stable.
-While group 15 has 5 electrons, it is easier for them to gain 3 electrons to become 8 electrons than losing all 5 electrons.
-the same thing for group 16 has 6 valence electrons and 17 has 7 electrons. It is easier for them to gain 2 and 1 more valence electrons to become stable.
Hope this helps!
what is the kinetic energy in chem
Answer:
Kinetic energy is the energy possessed by an object in motion.
what is the definition of sulphur
Answer:
the chemical element of atomic number 16, a yellow combustible nonmetal.
Explanation:
ur welcome plz give me brainliest
Explanation:
A pale-yellow, brittle nonmetallic element that occurs widely in nature, especially in volcanic deposits, minerals, natural gas, and petroleum. It is used to make gunpowder and fertilizer, to vulcanize rubber, and to produce sulfuric acid.
What percentage of the atmosphere is oxygen?
Answer:
21%
Explanation:
It's a mixture of different gases. The air in Earth's atmosphere is made up of approximately 78 percent nitrogen and 21 percent oxygen.
SCIENCEEEE!!!! I NEED HELPPP
How many total atoms are in the following compound: Ca(CO3)2H2
SnO₂ + 2H₂
+ 2 H2 → Sn + 2 H2O
Is it balanced or unbalanced
Answer:
I'm pretty sure it is unbalanced
10 examples of semi-metals
Answer:
boron.silicon.germanium.arsenic.antimony.tellurium.polonium.How can you separate sand, sugar and gravel
Answer:
Grating
Explanation:
I think you need to grate it
Answer: The sugar would dissolve in water. You could then pour off the solution and wash the remaining sand with a bit more water. Heat the water to evaporate it from the sugar, and the two are separate
Explanation:
A wave with a higher frequency has a longer wavelength
TRUE
FALSE
Answer:
FalseA wave with a higher frequency have a shorter wavelength, the higher the sound it, the closer the arcs of the wavelength are, the faster the sound is, the shorter they are.
According to scied.ucar.edu ~ "The frequency of a wave is inversely proportional to its wavelength. That means that waves with a high frequency have a short wavelength, while waves with a low frequency have a longer wavelength. Light waves have very, very short wavelengths."
Hope this helps
Explanation:
May I have brainliest please? :)
A wave with a higher frequency has a longer wavelength is a false.
Relation of frequency, energy and wavelengthA wave with a higher frequency has a longer wavelength is a false statement because shorter wavelength have higher frequency and also higher energy.
We know that longer wavelength of a wave having shorter frequency and shorter energy while on the other hand, the shorter wavelength of a wave having higher frequency and higher energy so we can conclude that the statement is false.
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i need help with scientific notation. this is the decimal notation form help.
Answer:
1.23345*10^11
5.768*10^(-5)
3.456*10^(-2)
2.28*10^9
8.0970*10^4
Explanation:
You just need to count the number of zeros and move the values backward and forward to get the scientific notation.
Acid rain is a type of pollution caused mainly from
fertilizer use
high concentrations of nitric and sulfuric acid from pollution
use of pesticides
CFC's
с
d
Answer:
im pretty sure its the second one
Where is it expected to find lava solidifying into basalt?
Answer:
at the center of the mid-ocean ridge
Explanation:
Answer:
Anywhere along the mid-atlantic ridge
Explanation:
It goes through a bunch of history, such as the Continental Drift Theory from Alfred Wegener to Harry Hess proving it. So, in WW2, Harry Hess was in the navy (he was a geographer/geologist who noticed while using sonar, that the waves were bouncing back uneven when they launched sonar, which proved the ocean floor was not flat like how they used to beleive it was.
Anyways, they discovered the mid-atlantic ridge, (you can see it on maps! Go to a search engine's maps and look at the atlantic ocean and you can see this weird ridges along with these (not latitude or longitude) lines.
The mantle in the Earth's layers is moving the plates (continental and oceanic plates to be exact) from convection currents, and there is very deep trenches in the Earth, such as the Mariana Trench. The mantle pushes magma through some holes, and it rises and cools in the ocean, which is then pushed aside by more solidifiying magma in a process called seafloor spreading. Magma is called lava when it comes out of the place where it comes from, so the lava cools into rock which is called basalt too.
Hope this helps anyone in the future!
I don't mean to be a boomer by necroposting
dont roast me plz
Who arranged the elements according to atomic mass and used the arrangement to predict the properties of missing element?
Answer:
Dmitri Mendeleev
Explanation:
Dmitri Mendeleev a Russian Chemist arranged elements on the periodic table according to their atomic mass. He used this arrangement to predict some of the properties of the missing element.
Dmitri Mendeleev around 1869 described the periodic table. The table was based on the periodic law which states that "chemical properties of elements are a periodic function of their atomic weights". In the Mendeleev table, elements are arranged by atomic weights with recurring properties in a periodic manner.In an atom, the number of neutrons is generally equal to or greater than the number of protons because....
Answer:
because the neutrons is always equal or greater there is never a less then in neutrons.
Explanation:hope this helped
In the reaction of Zn with HCl, 140.15 g of ZnCl2 was actually formed, although the theoretical yield
was 143 g. What was the percent yield?
Zn + 2HCl ➡ ZnCl2 + H2
Answer:
Percent yield = 98%
Explanation:
Given data:
Actual yield of ZnCl₂ = 140.15 g
Theoretical yield of ZnCl₂ = 143 g
Percent yield = ?
Solution:
Formula:
Percent yield = (actual yield / theoretical yield )× 100
Percent yield = (140.15 g/ 143 g)× 100
Percent yield = 0.98 × 100
Percent yield = 98%
what is the formula for
a. mercury (ll) nitride
b. Cobalt (ll) bromide
Answer:
a Hg(NO3)2
b CoBr2,CoBr2·6H2O,CoBr2·2H2O
Explanation:
Can you please help me it is urgent! A student is given a sample of an unknown liquid to test in the laboratory. The student thinks that the liquid is water. Which of the following properties of the sample is most helpful to determine if the liquid is water?
(A) color of the liquid
(B) mass of the liquid
(C) the volume of the liquid
(D) the boiling point of the liquid
Answer:
The answer is Boling Point
Explanation:
The properties of the sample which is most helpful to determine if the liquid is water is (D) . the boiling point of the liquid
What is Boiling Point ?
The boiling point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid and the liquid changes into a vapor.
The boiling point of a liquid varies depending upon the surrounding environmental pressure
Substances at different states usually possess certain properties that distinguishes them. For example, in this case involving a student who was given a sample of an unknown liquid to test in the laboratory, he thinks that the unknown liquid is water.
Specific properties of the unknown liquid can be used to identify whether it is water or not.
One property that can be used to ascertain whether or not it is water is the boiling point of the liquid. This is because specific liquids have specific boiling point. So if the unknown liquid has a boiling point of 100°C, then it can be ascertained to be water.
Therefore, The properties of the sample which is most helpful to determine if the liquid is water is (D) . the boiling point of the liquid
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What molecule contains a carbon atom with trigonal planar geometry?
Answer:
ethylene molecule. The molecule has trigonal planar geometry around its carbon atoms
Which statement best explains why an object appears green in sunlight?
A- The object absorbs most white light and refracts most green light.
B- The object refracts most white light and absorbs most green light.
C- More green light is absorbed while more red and blue light is reflected.
D- More green light is reflected while more red and blue light is absorbed.
Answer:
b
Explanation:
what charge must the particle be in the diagram and why? please help!
Answer:
It must be neutral because there are 9 positive atoms and 9 megative charged atoms they cancels each other out and make the particle neutral
Explanation:
I hope this helps!!
Find the celcius equivalent of 133 degrees Kelvin
Answer:
406 KExplanation:
To convert a temperature from degree Celsius to Kelvin add 273 to the value in degree Celsius
That's
K = 273 + °C
where
K is the temperature in Kelvin
°C is the temperature in degree Celsius
From the question we have
K = 273 + 133
We have the final answer as
406 KHope this helps you
Write a paragraph explaining what would happen if liquids A,B 3,C, and D were added to the graduated cylinder. Describe how the layers of the density column would be arranged (the order they would be in). Finally, predict where an object with a density of 1.07 g/cm^ 3 would stop in the column. Justify your reasoning with quantitative data (your density calculations).
Balance the following equation? Al + O2 - - - - - -) Al2O3
Answer:
4Al (s) + 3O₂ (g) → 2Al₂O₃
General Formulas and Concepts:
Chemistry - Reactions
Reaction PredictionBalancing RxN'sExplanation:
Step 1: Define RxN
Al (s) + O₂ (g) → Al₂O₃
Step 2: Balance RxN
4Al (s) + 3O₂ (g) → 2Al₂O₃
Need to balance the amount of oxygens on both sidesIf we balance the oxygens, the aluminums will also have to be rebalancedIn the reaction C + 02 - CO2, 18 g of carbon react with oxygen to produce 72 g of carbon dioxide. What mass of oxygen would be needed in the reaction? O 18 g O 54 g O 72 g 0 90 g
Mass of oxygen : 54 g
Further explanationConservation of mass applies to a closed system, where the masses before and after the reaction are the same
Reaction
[tex]\tt C+O_2\rightarrow CO_2[/tex]
mass before reaction = mass after reaction
mass C + mass O₂= mass CO₂
[tex]\tt 18~g+mass~O_2=72~g\\\\mass~O_2=72-18=\boxed{\bold{54~g}}[/tex]
How do you find the proton if you are given the mass and charge