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Which of these industrial processes typically involves electrolysis?
purifying water for drinking purposes
purifying copper to produce copper wiring for homes
neutralizing an acidic solution by adding a base
neutralizing a basic solution by adding an acid
Answer:
purifying copper to produce copper wiring for homes
Explanation:
Answer:
b.purifying copper to produce copper wiring for homes
Explanation:
An effective treatment for some cancerous tumors involves irradiation with "fast" neutrons. The neutrons from one treatment source have an average velocity of 3.5×107 m/s. If the velocities of individual neutrons are known to within 2.0% of this value, what is the uncertainty in the position of one of them?
Answer:
4.54 * 10^-14 m
Explanation:
From Heisenberg's uncertainty principle, we can write;
Δp.Δx ≥ h/4π
Given that;
Δp =Δmv
So;
Δmv.Δx ≥h/4π
Δmv =2/100(3.5×10^7 m/s * 1.66 * 10^-27)
Δmv =1.162 * 10^-21 Kgms-1
Δx ≥6.63 * 10^-34 /4 * 3.142 * 1.162 * 10^-21
Δx ≥4.54 * 10^-14 m
Use the periodic table to determine which of the
following could be an isotope of bromine (Br).
Check all that apply.
Z = 79, A = 196
Z = 35, A = 79
A = 79, N =44
D Z = 44, N = 44
DONE
16. Keesha performed a chemical reaction, and the products looked quite
different from the reactants. She knew the amount of matter had not
changed due to the law of conservation of mass. According to the law of
conservation of mass, what happens in a chemical reaction? *
Answer:
it's the third one
Explanation:
matter can't change, but mass can differ
Bubbles are released when nitric acid is added to a potassium carbonate solution.
What is the net ion
describe a difference in our inner planets and outer planets
What volume, in liters, does 128 grams of O2 occupy at STP?
89.6 L
22.4 L
67.2 L
44.8 L
Answer: 89.7 L
Explanation:
89.6 volume, in liters, does 128 grams of O2 occupy at STP. Therefore, option A is correct.
What do you mean by volume ?A volume is simply the amount of space taken up by any three-dimensional solid. A cube, a cuboid, a cone, a cylinder, or a sphere are examples of solids. Volumes differ depending on the shape.
Every three-dimensional object requires some amount of space. The volume of this space is measured. Volume is defined as the space occupied by an object within the boundaries of three-dimensional space. It is also known as the object's capacity.
1 mole Oxygen has mass 32 grams
Mole of Oxygen in 128 g mass = 128 g / 32 g/mol
= 4.0 mol O2
At Standard temperature and pressure this has volume
= 4.0 mol × 22.4 L/mol
= 89.6 L
Thus, 89.6 volume, in liters, does 128 grams of O2 occupy at STP, option A is correct.
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How many elements are in (NH4)3PO4
Answer:
4
Explanation:
There are 4 different elements in the compound (N, H, P, O) but if you want to count the number of each element then the answer is different.
In NH4, theres 1 N and 4 H, but since there are 3 NH4s then u have 3 N and 12 H. There's 1 P and 4 Os as well.
Added together u have 3 + 12 + 1 + 4 = 20 elements in total.
hope this helps!
What is the molecular mass for a non-electrolyte if 35.0 g of it is dissolved in 45.0 grams of water and the solutions boiling point is 101.25oC? (The KB for H2O is .51°C/m)
The boiling point of water increases as the amount of impurities dissolved in it increases. For our purposes, we will consider the non-electrolyte to be the dissolved impurity. The change in the boiling point can be calculated using the equation:
[tex]\Delta T_b = i \times K_b \times m[/tex]
where [tex]\Delta T_b[/tex] is the change in boiling point, [tex]i[/tex] is the van ‘t Hoff factor (whose value denotes the number of particles each formula unit of the dissolved substance dissociates into in water), [tex]K_b[/tex] is the boiling point elevation constant, and [tex]m[/tex] is the molality (moles of solute/kilogram of solvent) of the solution.
Right off the bat, since we're dealing with a non-electrolyte, the dissolved substance can be assumed not to dissociate in water. So, our van ‘t Hoff factor, [tex]i[/tex], would be 1 (by contrast, the [tex]i[/tex] for an ionic compound like NaCl would be 2 since, in water, NaCl would dissociate into two particles: one Na⁺ ion and one Cl⁻ ion). We're also given our [tex]K_b[/tex], which is 0.51 °C/m.
Assuming the normal boiling point of pure water to be 100 °C (a defined value for sig fig purposes), the change in boiling point from having dissolved 35.0 g of the non-electrolyte can be obtained by subtracting 100 °C from the final—elevated—boiling point of 101.25 °C:
[tex]\Delta T_b = 101.25\text{ }^o\text{C} - 100\text{ }^o\text{C} = 1.25\text{ }^o\text{C}[/tex]
Now, recall what we're asked to determine: the molecular mass of the dissolved substance. There is one unknown left in the equation: the molality of the solution. Let's first solve for that:
[tex]m = \frac{\Delta T_b}{K_b} = \frac{1.25^\text{ o}\text{C}}{0.51^\text{ o}\text{C}/m} \\ m = 2.45 \text{ mol solute/kg water}.[/tex]
Notice that we didn't include the i since its value is 1.
Now, what would happen if we multiplied our molality by the mass of water we've been given? We would be left with the moles of solute. And what are we asked to find? The molecular mass, or the mass per mole. We can accomplish this in two steps. Remember to convert your mass of water to kilograms:
[tex]2.45 \text{ mol solute/kg water} \times 0.045 \text{ kg water} = 0.110 \text{ mol solute.}[/tex]
And, finally, we divide the mass of our solute by the number of moles of solute:
[tex]\frac{35.0 \text{ g solute}}{0.110 \text{ mol solute}} = 317.5 \text{ g/mol}[/tex]
Our answer to two significant figures (which is the number of sig figs to which our [tex]K_b[/tex] is given) would be 320 g/mol.
A mixture of metals with properties different than the metals by themselves is called a(n) __________.
Answer:
Alloy
Explanation:
PLS HELP!!! i have no idea what this could be
Answer:
121.5g
Explanation:
from the equation:
2mol of Al react to give 3 mol of Zn
i.e 81g of Al will give 3×81/2 = 243/2 = 121.5g
___________ mL = 2.2 L
Answer:
2,200 mL I believe it is.
Answer:
2,200 is the answer of your question
CO2 + H2O --> C2H2 + O2
Answer:
C2H2 + 5 O2 = 4 CO2 + 2 H2O
Add / Edited: 27.09.2014 / 25.01.2015
Evaluation of information: 5.0 out of 5 / number of votes: 2
Source: https://chemiday.com/en/reaction/3-1-0-339
Explanation:
what kind of change is heating of mercuric oxide?
Answer:
Chemical change.
Explanation:
When it is heated it decomposes into mercury and oxygen gas. The mercury oxide reactant becomes the silver color of mercury. Hence, a color change can be noticed throughout the reaction.
Answer:
chemical change
Explanation:
What is the molar mass of methane (CHA)?
A. 16.05
grams
O B. 13.02 grams
O C. 49.05 grams
O D. 10 grams
The parts of the Earth that contain living organisms
Answer:
Biosphere
The Biosphere --contains all the planet's living things. This sphere includes all of the microorganisms, plants, and animals of Earth. Within the biosphere, living things form ecological communities based on the physical surroundings of an area.
Explanation:
Answer:
Biosphere
Explanation:The Biosphere --contains all the planet's living things. This sphere includes all of the microorganisms, plants, and animals of Earth. Within the biosphere, living things form ecological communities based on the physical surroundings of an area. hope this helps (:
9.
Which element is most likely to conduct heat and electricity?
A. Na B. Ca C.P D. Ne
Answer:
A. Na
Explanation:
Sodium is a good conductor of electricity and heat because it has only one electron in its valence shell.
i hope this helps :)
Answer:
C.) P
Explanation:
I believe this is correct, lmk if it's not.
how does a drupe fruit differ from a hesperidum fruit.
Answer:
hi
Explanation:
Answer:
Fleshy Fruits: All of most of the ovary wall (pericarp) is soft or fleshy at maturity. ... partitions, juicy seed vesicles, and a leathery exocarp similar to a hesperidium. ... This is a very common dry fruit found in many different plant families.
Explanation:
As you climb through the upper stratosphere, the temperature: increases decreases in constant
Answer:
It increases.
Explanation:
I hope this helps.
Answer:
Increases
Explanation:
Hope this helps :)
Match the special cases of each gas law with its description. A law may be used more than once. In the equations, K is a constant.
A. Boyle's law
B. Charles's law
C. Avogadro's law
D. Dalton's law
____ P1 V1 = P2 V2
____ V/T = k
____ V1 / T1 = V2 / T2
____ V = kn
____ PV = k
____ Ptotal = P1 + P2 + P3 + .
The special cases of gas laws and its description includes:
A. Boyle's law: P1 V1 = P2 V2
B. Charles's law: V/T = k or V1 / T1 = V2 / T2
C. Avogadro's law: V = kn
D. Dalton's law: Ptotal = P1 + P2 + P3 + .
What is gas law?Gas laws are laws that relate a gas's pressure, volume, and temperature. Boyle's law, named after Robert Boyle, states that the pressure P of a gas varies inversely with its volume V at constant temperature, or PV = k, where k is a constant. Charles' law is named after J. -A. -C.
They also include; Gay-Lussac's Law, Avogadro's Law and Dalton's law of partial pressures.
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is mending a broken bone chemical change and why(short answer pls)
Answer:
In a physical change, the substances involved retain their original properties. A new substance is not formed. A physical change can be reversed. Chemical changes happen on a molecular level when two or more substances chemically bond together.
Mending a broken bone is a chemical change as to heal the bone enzymes are released which are chemicals.
What is a chemical change?Chemical changes are defined as changes which occur when a substance combines with another substance to form a new substance.Alternatively, when a substance breaks down or decomposes to give new substances it is also considered to be a chemical change.
There are several characteristics of chemical changes like change in color, change in state , change in odor and change in composition . During chemical change there is also formation of precipitate an insoluble mass of substance or even evolution of gases.
There are three types of chemical changes:
1) inorganic changes
2)organic changes
3) biochemical changes
During chemical changes atoms are rearranged and changes are accompanied by an energy change as new substances are formed.
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if I have a +2 oxidation number do I give up or accept electrons?
Answer:
I will give up the electrons
Explanation:
Consider the following rules:
1. An atom loses electrons if its oxidation number is positive.
2. An atom gains electrons if its oxidation number is negative.
3. An atom neither gains nor loses electrons if its atomic number is zero.
As I have an oxidation number [tex]+2[/tex] that is oxidation number is positive, so, I will give up electrons.
6. A car is driving in a large circle at a constant speed of 20 miles per hour. Is the car accelerating? How do you know?
The car is not accelerating, because the car is driving at a constant speed of 20 miles per hour.
which one of these is NOT a unit for a reaction rate. 1) g/mL 2) M/min
The useful energy a light bulb gives out is
(a). kinetic energy (b) chemical energy (c) light energy
science subject
Answer:
Light bulb gives light energy which is usefull
Answer:
(c) light energy
Explanation:
As bulb is used for giving light and hence the energy that it gives is light energy.
Which of the following has the smallest atomic radius?
a B
b Al
c F
d N
e Ga
Answer:
c. F
Explanation:
As you go top to bottom down a column of the periodic table, atomic radius increases.
As you go left to right across a period of the periodic table, atomic radius decreases.
Knowing this trend, that means that the smallest atomic radius would be located in the top right of the periodic table. The closest element to that point is fluorine, or answer C.
2H20 → 2H2 + O2
Type of reaction?
Answer:
Notice how the elements splitIt is a decomposition reaction I do exams and quizzes if ur interestedHow does Natural selection lead to the Evolution of bacteria?
Answer:
Bacteria can evolve quickly because they reproduce at a fast rate.
Explanation:
Bacteria can evolve quickly because they reproduce at a fast rate. Mutations in the DNA of bacteria can produce new characteristics. A random mutation might cause some bacteria to become resistant to certain antibiotics, such as penicillin.
How many moles is 118 grams of Argon
Answer:
[tex]\boxed {\boxed {\sf About \ 2.96 \ moles \ of \ Argon}}[/tex]
Explanation:
To convert from grams to moles we must use the molar mass, which is found on the Periodic Table.
Argon: 39.9 g/molUse the molar mass as a ratio.
[tex]\frac{39.9 \ g \ Ar}{1 \ mol \ Ar}[/tex]
Multiply by the given number of grams: 118
[tex]118 \ g \ Ar *\frac{39.9 \ g \ Ar}{1 \ mol \ Ar}[/tex]
Flip the fraction so the grams of argon will cancel each other out.
[tex]118 \ g\ Ar * \frac{1 \ mol \ Ar}{39.9 \ g \ Ar}[/tex]
[tex]118 * \frac{ 1 \ mol \ Ar}{39.9 \ g \ Ar}[/tex]
[tex]\frac {118 \ mol \ Ar }{ 39.9 }[/tex]
[tex]2.95739348 \ mol \ Ar[/tex]
The original measurement of grams had 3 significant figures, so our answer must have 3 sig figs.
For the number we calculated, that is the hundredth place. The 7 in the thousandth place tells us to round the 5 to a 6.
[tex]2.96 \ mol \ Ar[/tex]
There are about 2.96 moles of Argon in 118 grams.