This question is describing an spectrophotometry experiment in which the concentration of copper(II) ions has to be determined when 2.50 g of a copper-rich penny is reacted with 50.0 mL of nitric acid. In addition, the absorbance of a sample of the solution turned out to be 0.12 at 635 nm, so that the concentration was estimated as 12.8 g/L.
First of all, we must recall the Beer's law that can be written as follows:
[tex]A=ebC[/tex]
Whereas A is the absorbance of the sample, e the molar absorptivity, b the cuvette's path and C the concentration. However, this problem is not providing sufficient information to calculate the required concentration, however, similar absorbance experiments have graphed (absorbance vs concentration) calibration curves exhibiting trendlines as the one shown below:
[tex]y=0.009647x-0.003655[/tex]
Thus, since y stands for the absorbance and x for the concentration but in g/L not M (mol/L) for those experiments, we can set y equal to 0.12 so we solve for x as the concentration of the copper(II) ions in the sample:
[tex]y=0.009647x-0.003655\\\\x=\frac{0.12+0.003655}{0.009647}\\\\x=12.8g/L[/tex]
Nevertheless, it would be great if you come up with your own trendline, having clear the units for the absorbance vs concentration graph and thus double check your results because the data was not enough for the time being.
Learn more:
(Beer's law and trendlines) https://brainly.com/question/5093710(Spectrophotometry) https://brainly.com/question/14467788what happens when you combine hydroxide, chlorine, and 2 drops of h2o
Answer:
Chlorine will react in water to form hypochlorous acid, which can then dissociate into hydrogen and hypochlorite ions, according to Eqn (1). This reaction is very important, as the disinfecting power of HOCl, hypochlorous acid, is about 40–80 times that of OCl−, hypochlorite.Explanation:
CARRY ON LEARNINGAND REMEMBER DO ALWAYS READ AND WRITE
1.
Light is a(n) _______wave.
Group of answer choices
A. longitudinal
B. large
C. ocean
D. transverse
Answer: D. transverse
Explanation:
Light is a transverse wave, while sound is a longitudinal wave.
What is the role of starch in the titration reaction?
Answer:
Starch reacts with Iodine in the presence of Iodide ion to form an intensely colored blue complex, which is visible at very low concentrations of Iodine, making it a very good indicator in both direct and indirect lodometric titrations.
Explanation:
hope this helps
A 4.190 g sample of an oxide of chromium contains 2.179g of chromium, what is its empirical formula?
a. CrO2
b. Cr2O
c. CrO3
d. Cr2O3
I'm not sure but I think it is C. CrO3
what is the mass in g of 7.009 x 10^21 molecules of Pl3?
Write the symbol for every chemical element that has atomic number greater than 3 and atomic mass less than 15.4 u.
Answer:
N, B, Be, C
Explanation:
N (Nitrogen) has 14.0067 B (Boron) has 10.81 Be (Beryllium) has 9 and C (Carbon) has 12
The symbols for every chemical element that has atomic number greater than 3 and atomic mass less than 15.4 u are C, N, O, F, and Ne.
To find elements with atomic number greater than 3 and atomic mass less than 15.4 u, we'll consider the periodic table. Elements with atomic numbers 4 (Be) and higher meet the atomic number criterion. For the atomic mass, we'll look at elements with atomic masses below 15.4 u.
The chemical elements that fulfill both criteria are: Carbon (C) with atomic number 6 and atomic mass 12.01 u, Nitrogen (N) with atomic number 7 and atomic mass 14.01 u, Oxygen (O) with atomic number 8 and atomic mass 16.00 u, Fluorine (F) with atomic number 9 and atomic mass 18.99 u, and Neon (Ne) with atomic number 10 and atomic mass 20.18 u.
These elements meet the conditions of having atomic number greater than 3 and atomic mass less than 15.4 u. Therefore, the symbols for these elements are C, N, O, F, and Ne.
To learn more about atomic number here
https://brainly.com/question/31040816
#SPJ3
Which population will increase?
Answer: World 5,306,425,000 6,895,889,000 7,503,828,180
1 China 1,139,060,000 1,341,335,000 1,384,688,986
2 India 873,785,000 1,224,614,000 1,296,834,042
3 United States 253,339,000 310,384,000 329,256,465
Explanation:
You have 15 grams of of MgSO4, how
many moles of MgSO4 do you have?
A 0.125 Moles of MgSO4
B 0.75 Moles of MgSO4
C 7.5 Moles of MgSO4
D 15.88 Moles of MgSO4
Answer:
C 7.5 Moles of MgSO4
Explanation:
pa help thank yoeee <3333
Answer:
1.c
2.c
3.a
4.b
5.a
i think that's the answer
Covalent compounds are generally not very hard. Justify the statement.
Covalent compounds are generally not very hard because they are formed by two or more nonmetallic atoms.
COVALENT COMPOUNDS:Covalent compounds are compounds whose constituent elements are joined together by covalent bonds.
Covalent bonding occurs when two or more nonmetallic atoms of an element share valence electrons. This means that covalent compounds will not be physically hard since they constitute non-metals.
Examples of covalent compounds are:
H2 - hydrogenH2O - waterHCl - hydrogen chlorideCH4 - methaneLearn more about covalent compounds at: https://brainly.com/question/21505413
A block has 73 kg is being pushed and accelerated at rate of 10 m/s. what force is being applied to the block?
730 N
7.3 N
7300 N
730 Kg
Answer:
730 N
Explanation:
force =mass ×acceleration
force= 73kg×10m/s
F=730N
Select True or False: Consider the reaction N2(g) 3H2(g) 2NH3(g). The production of ammonia is an exothermic reaction. When heat is added to the equilibrium system it will shift to increase the amount of ammonia produced.
Answer:
False
Explanation:
As I like to think of it, equilibrium will shift either 'forwards' (to increase products) or 'backwards' (to increase reactants) to oppose any change in system;
If heat is added, the equilibrium will shift in the direction that reduces heat within the system;
In other words, it will shift in favour of the endothermic reaction, i.e. the reaction where heat is gained by the molecules/atoms and therefore taken out from the system;
If the 'forwards' reaction, producing NH₃, is exothermic (i.e. energy is released in the reaction), then the 'backwards' reaction is endothermic;
So the equilibrium will shift in this direction, which is the reaction of 2 NH₃ molecules producing N₂ and 3 H₂
2). How are simple carbohydrates, like glucose, used to build starches?
Carbohydrates which include sugars and starches are the primary energy sources produced in plants and used by heterotrophic organisms.
Carbohydrates are composed of a basic chemical formula that typically contains a ratio of one Carbon atom for every two Hydrogen atoms and one Oxygen atom C1H2O1. Basically one carbon atom for every one water molecule Carbon + Water = Carbohydrate.
Monosaccharides or Single Carbon Chain Sugars include Glucose C6H12O6
Disaccharides or Double Carbon Chain Sugars include Sucrose C12H22O11
Combining monosaccharides and disaccharides create Polysaccharides which are complex sugars called starches.
The temperature went from 25 to 90 degrees Celsius. What is the CHANGE in temperature?
Answer:
+65 degress ?
Explanation:
I feel like there is more to this question
WHICH ONE?????????????????? Brainlest
Answer:
I believe it would be C, The number of atoms in the reactants is equal to the number of atoms composing the products
Explanation:
hope this helps! :D
have a miraculous day!! <3
Answer:
The number of atoms in the reactants is equal to the number of atoms composing the products
4) If an object is traveling at a speed of 400 m/s, how long (in hours) will it take to reach 950.5 km?
A) 3.96 x 10-2
B) 1.43 x 105
C) 6.34
D) 39.6
E) 7.01 x 10-6
Answer:
Answer: 0.66 hours
Explanation:
[tex]{ \rm{time = \frac{distance}{speed} }} \\ \\ { \rm{time = \frac{(950.5 \times 1000) \: m}{400 \: m {s}^{ - 1} } }} \\ \\ { \rm{time = {2376.25 \: s}}}[/tex]
• Remember 1 second accounts for 1/3600 hours
[tex]{ \rm{time = \frac{2376.25}{3600} }} \\ \\ { \rm{time = 0.66 \: hours}}[/tex]
The time taken by object traveling at a speed of 400 m/s to reach 950.5 km distance is 0.66 hr or 39.6 min.
What is average velocity ?
Average velocity is given by the total distance covered by the object in total given time. SI unit of velocity is m/s.
Here in this question it is given that the object is travelling with speed v of 400 m/s and it is to find the time t to reach 950.5 km distance d.
it is known that 1 km = 1000 m
that is 950.5 km = 950500 m
Now, using the relation of speed-distance to find time t to reach 950.5 km distance :
[tex]\begin{aligned}v&=\frac{d}{t}\\t&=\frac{d}{v}\\&=\frac{950500}{400}\\&=2376.25 \text{ s}\end{aligned}[/tex]
Now converting 2376.25 sec into hrs by dividing it by 3600 we get :
2376.25/3600 = 0.66 hr or 39.6 min.
Therefore, the time taken by object to reach 950.5 km distance is 0.66 hr or 39.6 min.
Learn more about "speed" here:
https://brainly.com/question/7359669
#SPJ2
How many grams of NaOH is needed to neutralize 90 mL of 1.5 N HCl?
mol = conc × v
= 1.5 × 0.09
= 0.135 moles of HCl
HCl + NaOH > NaCl + H2O
1 mole HCl = 1 mole NaOH
0.135 mol HCl = x
x = 0.135 mol NaOH
mass = mol × molar mass
= 0.135 × 40
= 5.4 g
NaOH = 23 + 16 + 1 = 40 g/mol
I'm not a 100% sure if it's correct
A block has 73 kg is being pushed and accelerated at rate of 10 m/s. what force is being applied to the block?
A-730 N
B-7.3 N
C-7300 N
D-730 Kg
Answer:
730 N
Explanation:
force =mass×acceleration
force= 73kg × 10 m/s
f=730N
What is the theoretical amount of sodium citrate (Na3C6H5O7) produced if you react 85.0g of citric acid (H3C6H5O7) in excess amount sodium hydroxide? If you actually produced 97.3 g of sodium citrate what is the percent yield?
Answer:
i did not find the amswer sorry
[tex]{ \red {\sf{Define \: Transportational}}}[/tex]
2+x=19
Find x
Easy!!
2+17=19
#hope that helps
Answer:
To find the answer you may
2+17=19
Explanation:
so that is the answer I'm sorry,to not give all the solutions
I’m not sure if it’s the square on the right or left. Please help
Answer:OK im not 100% sure but it should be the right one
Explanation:
Calculate the mass percentage of each element in aluminum oxide.
Answer:
So, Percentage Composition of Aluminium = 2778×100%=34.62% (approx.) Percentage Composition of Oxygen = 3×1678×100%=61.54% (approx.)
what is the molecular geometry of AsCl3?
Molecules' general shape, as well as bond lengths, bond angles, torsional angles, and any other geometrical factors that affect each atom's position, are revealed by their molecular geometry. The molecular geometry of AsCl₃ is trigonal pyramidal.
Molecule geometry is the study of the three-dimensional configuration of the atoms that make up a molecule. Because the shared pairs of electrons remain localized in a specific location between the nuclei of the involved atoms, covalent molecules have directed bonds.
The arsenic atom is surrounded by 4 regions of electron density which means that it has a steric number equal to 4. According to VSPER Theory, the molecular geometry will be trigonal pyramidal, AX₃E₁.
To know more about molecular geometry, visit;
https://brainly.com/question/31383201
#SPJ6
What kind of intermolecular forces act between two chloramine (NH2CI) molecules?
Explanation:
brain and heart froce acts between two chloramine
Answer:
Dispersion, Hydrogen-bonding, and Dipole forces act between two chloramine (NH2CI) molecules.
Explanation:
Dispersion is exerted between all molecules. Chloramine is polar, therefore dipole forces are present. The molecular geometry of chloramine (NH2Cl) is a trigonal pyramidal, therefore hydrogen-bonding forces are present.
What volume of 0.826 MKOH solution do you need to make 3.74 L of a solution with a pH of 12.500?
Given that –
pH = 12.5We know that –
pH + pOH = 14Then –
[tex]\qquad[/tex][tex]\bf\longrightarrow pOH = 14 -12.5 [/tex]
[tex]\qquad[/tex][tex]\sf \longrightarrow pOH = 1.5[/tex]
[tex]\qquad[/tex][tex]\sf \longrightarrow [OH^- ] = 10^{-1.5 }[/tex]
[tex]\qquad[/tex][tex]\bf \longrightarrow [OH^-] = 3.16 × 10^{-2}[/tex]
Now the number of moles of KOH need to ensure that concentration of Hydroxide anions is equal to –
[tex]\qquad[/tex][tex]\bf \longrightarrow 3.74\: L \times \dfrac{3.16× 10^{-2}}{1 \: L }[/tex]
[tex]\qquad[/tex][tex]\bf \longrightarrow 1. 18 × 10^{-1 }M [/tex]
Volume of the solution contains the need number of moles of Hydroxide anions –
[tex]\qquad[/tex][tex]\sf \longrightarrow \dfrac{ 1.18×10^{-1} \: moles \: OH^-}{0.826 \: moles \: OH^-}[/tex]
[tex]\qquad[/tex][tex]\sf \longrightarrow 0.143 L [/tex]
[tex]\qquad[/tex][tex]\sf \longrightarrow 0.143 \times 1000[/tex]
[tex]\qquad[/tex][tex]\pink{\bf\longrightarrow 143 mL }[/tex]
______________________________________
2.
The highest part of the wave is called the ____________.
Group of answer choices
A. best
B. crest
C. top
D. trough
Answer:
B. crest
Explanation:
The highest part of a wavelength is called the crest, meanwhile, the lowest part is the trough.
Answer:
b
Explanation:
it's highest because it have the most higher wave
Most rain falls _____________________.
on land
in freshwater lakes, rivers, and streams
on the oceans
on the polar ice caps
Answer:
I think it is a)in freshwater lakes,rivers,and stream
Answer:
a) in freshwater lakes, rivers, and streams
#keep learning :)Need asap thank you
Answer:
c.boron-11
Explanation:
The atomic mass of boron is 10.81 u.
And 10.81 u is a lot closer to 11u than it is to 10u, so there must be more of boron-11.
To convince you fully, we can also do a simple calculation to find the exact proportion of boron-11 using the following formula:
(10u)(x)+(11u)(1−x)100%=10.81u
Where u is the unit for atomic mass and x is the proportion of boron-10 out of the total boron abundance which is 100%.
Solving for x we get:
11u−ux=10.81u
0.19u=ux
x=0.19
1−x=0.81
And thus the abundance of boron-11 is roughly 81%.
true or false a change in state of matter would be considered a physical change
Answer:
true
Explanation:
Because the changes in state of matter would be considered
1. Here is a chemical equation: C2H2 + O2 → CO2 + H2O
• A Balance this chemical equation.
• B State what type of chemical reaction this is.
• C What will happen during this reaction besides just CO2 and H2O being released.
• D Discuss how your balanced chemical equation agrees with the law of conservation of mass.
2. Balance each of the reactions listed below. What type of reactions are they? Single-displacement, double-displacement, synthesis, decomposition, or combustion reaction.
• A Na + Cl2 → NaCl
• B Fe + O2 → FeO
Answer:
1) a) 2 C2H2 + 3O2 --> 2CO2 + 2H2O
b) Combustion Reaction
c) Bonds will be broken on the reactant side which will require energy.
d) It agrees with the law of conservation of mass because there are the same amount of molecules of each element on both sides of the equation, meaning mass was not created nor destroyed.
2) a) 2Na + Cl2 --> 2NaCl
Synthesis
b) 2Fe + O2 --> 2FeO
Synthesis
Hope this helps!
Explanation:
To calculate the atoms of an element in a given molecule, we need to multiply stoichiometry by the number that is written on the foot of that element. Therefore, the balanced equation is
2 C[tex]_2[/tex]H[tex]_2[/tex]+ 3O[tex]_2[/tex] [tex]\rightarrow[/tex] 2CO[tex]_2[/tex]+ 2H[tex]_2[/tex]O
What is Balanced equation?Balanced equation is the one in which the total number of atoms of a species on reactant side is equal to the total number of atoms on product side. The mass of the overall reaction should be conserved. There are so many types of chemical reaction reaction like combination reaction, displacement reaction.
a) 2 C[tex]_2[/tex]H[tex]_2[/tex]+ 3O[tex]_2[/tex] [tex]\rightarrow[/tex] 2CO[tex]_2[/tex]+ 2H[tex]_2[/tex]O is the balanced equation
b)Reaction is a Combustion Reaction
c) energy is required for the breaking of bond.
d) It agrees with the law of conservation of mass as the number of atoms of each element on reactant and product side is same.
Therefore, the balanced equation is
2 C[tex]_2[/tex]H[tex]_2[/tex]+ 3O[tex]_2[/tex] [tex]\rightarrow[/tex] 2CO[tex]_2[/tex]+ 2H[tex]_2[/tex]O
Learn more about the balanced equation, here:
https://brainly.com/question/7181548
#SPJ2