Answer: 21.3, 3 sig figs, units certain, tenths uncertain
Explanation:
The temperature is 21.3 degrees Celsius, This temperature has 3 significant figures. The smallest certain digit is in the tenth place and the uncertain digit is in the decimal place.
What are significant figures?
The number that is given as digits is established using significant figures. A meaningful representation of numbers is carried by these digits. Frequently, significant numbers are employed in place of figures. By counting all of the values beginning with the first non-zero digit on the left, we may determine the number of significant digits. 12.45, for instance, contains four significant numbers.
Therefore, in the above observation, the temperature is 21.3 degrees Celsius, This temperature has 3 significant figures. The smallest certain digit is in the tenth place and the uncertain digit is in the decimal place.
Read more about significant digits, here
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CuBr(s)⇄Cu+(aq)+Br−(aq)
Shown above is the chemical equation for the dissolution of the slightly soluble salt CuBr(s). Its Ksp value in pure water was experimentally determined. CuBr was found to be much less soluble in a 0.001MNaBr solution than in pure water. Which of the following correctly explains the decrease in solubility of CuBr in 0.001 M NaBr?
A.)The concentration of water is much less in the NaBr solution than in pure water, reducing the rate of dissolution of the salt.
B.)The presence of Na+ ions in the solution inhibits the dissolution of salts.
C.)The presence of additional Br− already in the solution decreases the value of the Ksp for CuBr , causing the solubility to decrease.
D.)The presence of additional Br− ions already in the solution means equilibrium will be reached when much less CuBr has dissolved.
Answer:
D) The presence of additional Br- ions already in the solution means equilibrium will be reached when much less CuBr has dissolved.
Explanation:
CuBr ⇄ [tex]Cu^+[/tex] + [tex]Br^-[/tex]
Because there is Br- in CuBr, when put into solution, those Br- ions become part of the products side of the equation, shifting the equilibrium back towards the CuBr side, meaning less CuBr will dissolve.
The decrease in the solubility of the CuBr in NaBr solution has been due to the presence of additional Br ions in the solution. Thus option C is correct.
The equilibrium position has been the condition when the concentration of the reactants and products has been equal. The solubility of the CuBr has been dependent on the ksp for the solution.
The ksp has been the solubility product and has been dependent on the concentration of the reactants. The NaBr solution will be dissociated in the form of Na ions and Br ions. The dissolution has been based on the equilibrium of the CuBr.
With the presence of additional Br ions, the equilibrium of the CuBr solution has been reached earlier, and thereby the solubility of the solution has been decreased.
The decrease in the solubility of the CuBr in NaBr solution has been due to the presence of additional Br ions in the solution. Thus option C is correct.
For more information about solubility, refer to the link;
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Which of the following is not a chemical change?
a. paper being shredded
b. steel rusting
c. charcoal burning
d. a newspaper yellowing in the sun
Answer:
paper being shredded
Explanation:
Answer:
its A
Explanation:
how many grams are in 5.12 moles of Al
Answer:
138.14547456
Explanation:
How many moles Aluminium in 1 grams? The answer is 0.037062379468509.
We assume you are converting between moles Aluminium and gram.
You can view more details on each measurement unit:
molecular weight of Aluminium or grams
The molecular formula for Aluminium is Al.
The SI base unit for amount of substance is the mole.
1 mole is equal to 1 moles Aluminium, or 26.981538 grams.
Note that rounding errors may occur, so always check the results.
Use this page to learn how to convert between moles Aluminium and gram.
Answer:
[tex]\boxed {\boxed {\sf About \ 138 \ grams \ of \ aluminum}}[/tex]
Explanation:
To convert from moles to grams, we must use molar mass.
This can be found on the Periodic Table, so look for the symbol for aluminum: Al
Al: 26.981538 g/molWe can use this number as a ratio.
[tex]\frac { 26.981538 \ g \ Al} { 1 \ mol \ Al}[/tex]
Multiply by the given number of moles: 5.12
[tex]5.12 \ mol \ Al *\frac { 26.981538 \ g \ Al} { 1 \ mol \ Al}[/tex]
Multiply. The moles of aluminum will cancel.
[tex]5.12*\frac { 26.981538 \ g \ Al} { 1}[/tex]
[tex]138.145475 \ g \ Al[/tex]
Round. The original measurement of moles has 3 significant figures, so our answer must also have 3 sig figs.
For the number we calculated, that is the ones place. The 1 in the tenth place tells us to leave the 8.
[tex]138 \ g \ Al[/tex]
There is about 138 grams of aluminum in 5.12 moles.
HELP help HELP!!!! Me ME me
when a liquid is cooled the kinetic energy of the particles a)decrease b) increase c) stay the same
Answer:
a) decrease
Explanation:
Hope this will help
Where did the zebra mussels originally come from?
Answer:
he ocean
Explanation:
They are sea cretures who origanly lived in water (or near i forgot)
What is the air we breathe composed of?
Answer:
oxygen
Explanation:
A pure sample of gold has a volume of 25.0 cm3 and a mass of 483 g. What is the density of gold?
Answer:
19.4 g/cm^3
Explanation:
Hey
here to help and to serve
Answer:
lol thx
Explanation:
how many oxygen atoms are in 1 mol of CO2
Answer: 2 atoms
Explanation: A molecular formula of the compound carbon dioxide is CO 2 . One molecule of carbon dioxide consists of 1 atom of carbon and 2 atoms of oxygen.
53.0 g of silver (1) nitrate reacts according to the reaction shown below:
AgNO3 + KCI — AGCI + KNO3
Find the theoretical yield of AgCl. If the amount of AgCl actually produced is 38.5 grams,
what is the percent yield of the experiment?
Answer:
Percent yield = 86.09%
Theoretical yield of AgCl = 44.72 g
Explanation:
Given data:
Mass of silver(1) nitrate = 53.0 g
Actual yield of AgCl = 38.5 g
Theoretical yield of AgCl = ?
Percent yield = ?
Solution:
Chemical equation:
AgNO₃ + KCl → AgCl + KNO₃
Number of moles of AgNO₃:
Number of moles = mass/molar mass
Number of moles = 53.0 g/ 169.87 g/mol
Number of moles = 0.312 mol
now we will compare the moles of AgNO₃ and AgCl
AgNO₃ : AgCl
1 : 1
0.312 : 0.312
Theoretical yield of AgCl:
Mass = number of moles × molar mass
Mass = 0.312 mol × 143.32 g/mol
Mass = 44.72 g
Percent yield:
Percent yield = (actual yield / theoretical yield) × 100
Percent yield = ( 38.5 g / 44.72 g ) × 100
Percent yield = 86.09%
Why can a solution be classified as a mixture?
Both are always homogeneous.
It is made up of only one substance.
Both are made up of two substances that are not chemically combined.
Both are made up of two substances that are chemically combined.
Answer:
Both are made up of two substances that are not chemically combined.
Explanation:
Solutions can be classified as a mixture because both are made up of two substances that are not chemically combined.
A mixture is made up of the following properties:
They have an indefinite composition. Their constituents retain their physical properties. They can easily be separated into their physical constituents.Solutions share this property with all mixtures.
The constituent of a solution are not chemically combined or bonded together
Answer:
c
Explanation:
I go to k12 (or you) If you go to k12 this is correct
Section
1
2
7)
Given the equation representing a reaction:
203Pb + 5921 TECn + on
3
4
5
Which type of reaction is represented by this equation?
6
A)
neutralization
8
-9
B)
polymerization
C)
substitution
10
11
12
13
= 14
- 15
16
-17
D)
transmutation
18
19
20
21
Answer:
a
Explanation:
neutalize acidity level
When a substance changes from solid to liquid form, the bonds between the particles become
stronger.
True
False
Answer:True
Explanation:
Answer:
False
Explanation:
Its false, the bonds become weaker.
Which force is equal but opposite to the one shown?
Answer:B
Explanation:
Which phrase best describes an apple?
a. heterogeneous mixture
b. homogeneous compound
c. heterogeneous substance
d. homogeneous mixture
chemical equation for cycloheptane (l)
Answer: C7H14 - PubChem.
Explanation:
How often is Earth's surface being changed?
1 every hundred years
2 never
3 at all times
4 once a year
Answer:
I believe it is 3.
Explanation:
because the earth is constantly shifting.
In a reaction process a company expected to make 6.8
tonnes of ammonia but the yield of ammonia was
only 4.2 tonnes. Calculate the percentage yield of
ammonia.
1
61.8 %
2
0.6 %
3
16.2%
4
6.2 %
Answer:
1) 61.8%
Explanation:
(4.2/6.8)*100
__C + __H2O → __CO + H2
Answer:
It is balanced
Explanation:
There is 1 Carbon, 2 Hydrogen, and 1 Oxygen on the right and 1 Carbon, 1 Oxygen and 2 Hydrogen on the left. This equation is balanced.
Please help me i am very lost
Calculate the salinity of the liquids in the table. Round your answers to one decimal place.
$\frac{\text{mass of salt}\left(g\right)}{\text{mass of solution}\left(g\right)}\times1000=salinity\left(ppt\right)$mass of salt(g)mass of solution(g) ×1000=salinity(ppt)
Sample Solution Mass of Salt (g) Mass of Solution (g) Salinity (ppt)
A
27
1000
B
15
850
C
94
2355
D
11
3796
Answer:
i think that's number D.
How much energy is required to heat up a Styrofoam cup from 25oC to 40oC? The mass of the cup is 20 grams and the specific heat capacity of Styrofoam is 1.1 J/(g *oC). Group of answer choices
Answer:
[tex]Q=330J[/tex]
Explanation:
Hello!
In this case, since the energy involved during a heating process is calculated as shown below:
[tex]Q=mC(T_2-T_1)[/tex]
Whereas we consider the mass, heat capacity and temperature; we are able to plug in the given data to obtain:
[tex]Q = 20g*1.1\frac{J}{g\°C}(40\°C-25\°C)\\\\Q = 330J[/tex]
Best regards!
Close friendships at work are often bad for the business. true or false and why?
Explanation:
true true true true true true
Answer:
False
Explanation:
Because that is your friend and your friend is helping you in other things that you need some help.
Explain what is a chemical reaction.
Answer:
Chemical reaction, a process in which one or more substances, the reactants, are converted to one or more different substances, the products. Substances are either chemical elements or compounds. A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.
Explanation:
Answer:
a process in which one or more substances, the reactants, are converted to one or more different substances, the products. Substances are either chemical elements or compounds. A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.
Explanation:
Here's an example. When you burn wood, It releases Carbon dioxide, water vapor, and ashes. It just depends what chemicals you use ^^
Jesim wants to help Nancy understand the movement that happens during one Earth year, Jassim holds a small globe representing Earth, and Nancy holds a large ball representing the Sun. What should Jessim do to show
Nancy what happens during one Earth year?
Jessim should not move except to slowly spin the globe
Jesim should slowly spin the globe and walk away from Nancy
Jessim should have Nancy walk around him while spinning the ball
Jessim should spin the globe quickly while walking in a circle around Nancy
Answer:
The answer is D jessim should spin the glove quickly while walking in a circle around nancy.
Explanation:
A simple circuit with a battery connected to a buzzer by electrical wires is placed on a table. When the buzzer sounds, the table begins to ratte. Which form of energy makes the table rattle?
chemical
ОО
electrical
heat
mechanical
Answer:
Mechanical
Explanation:
mechanical energy:
energy that an object has
because of its motion or
position
Crystal needs more protein in her diet. Which food sources will best provide the building blocks she needs?
Which of the following chemical formulas show three molecules of a compound that has one
NEED FAST
atom of mercury and two atoms of bromine
1. 3Mc2Br
2. Hg3Br2
3. 3McBr2
4.McBr23
5.3HgBr2
6.3Hg2Br
The chemical formula : 3HgBr₂(Mercury(II) bromide)
Further explanationGiven
The chemical formulas of Mercury and Bromine
Required
The appropriate chemical formula
Solution
A molecular formula is a formula that shows the number of atomic elements that make up a compound.
The number of molecules is determined by the coefficient in front of the compound
the number of atoms is determined by the subscript after the atom and the coefficient
Three molecules⇒ coefficient = 3
one atom of Mercury ⇒Hg
two atoms of Bromine ⇒ Br₂
The chemical formula : 3HgBr₂
100 POINTS AND BRAINLIEST FOR HELP
Write a paragraph that explains diffusion and osmosis and how it relates to the circulatory system. Each sentence should be typed in the appropriate color.
It should include an introductory sentence that restates the question. A sentence that explains diffusion. A sentence that explains osmosis and at least 2-3 sentences that explain the relationship between diffusion, osmosis and the circulatory system. And, lastly, a conclusion sentence.
Materials are transferred between individual cells and their internal environment through the cell membrane by diffusion, osmosis, and active transport. During diffusion and osmosis, molecules move from a higher concentration to a lower concentration. Osmosis: Osmosis is the movement of solvent particles across a semipermeable membrane from a dilute solution into a concentrated solution. Diffusion: Diffusion is the movement of particles from an area of higher concentration to lower concentration. This would be the diffusion.
At what temperature in Kelvin will 0.1243 moles of fluorine exert a pressure of 2.02 atm at a volume of
0.625 L? Answer: 124K
How do I solve this?
Answer:
Explanation:
The formula would be PV=nRT but since were trying to find temp. the formula becomes T=PV/nR (n is the # moles and R is the ideal gas constant which equals 0.0821 for this)
The formula becomes T= 2.02 x 0.625 divided by 0.1243 x 0.0821 then just solve that in the calculator and u get 123.7K or 124K