Answer:
72 million because they needed to raise cash for its development
Explanation:
It is a known fact that at lunch Ethereum had only 72 million tokens in existence back in July 2015. In other to develop the Blockchain network further, the founder, Vitalik Buterin organized a fundraising event around July and August 2014.
Fast forward to the year 2020, Ether now has a total supply of about 112 million.
Calculate the percent composition for each of the elements in Na3PO4. A 5.00 gram sample of an oxide of lead PbxOy contains 4.33 g of lead. Determine the simplest formula for the compound. Balance the following equations by inspection: Cu(N03)2 rightarrow CuO + NO2 + O2 C2H6 + O2 rightarrow CO2 + H2O Mg3N2 + H2O rightarrow Mg(OH)2 + NH3 Magnesium (Mg) reacts with chlorine gas (C12) to produce magnesium chloride (MgC12). How many grams of Mg will react with 2 moles of Cl2? Mg(s) + C12(g) rightarrow MgC12(s) The compound P4S3 is used in matches. It reacts with oxygen to produce P4O10 and SO2. The unbalanced chemical equation is shown below, P4S3(s) + O2(g) rightarrow P4O10(s) + SO2(g) What mass of SO2 is produced from the combustion of 0.331 g P4S3 in excess O2? Nitric oxide is made from the oxidation of ammonia. What mass of nitric oxide can be made from the reaction of 8.00 g NH3 with 17.0 g O2? 4 NH3(g) + 5 O2(g) rightarrow 4 NO(g) + 6 H2O(g) To what volume should you dilute 50.0 mL of 12 M HNO3 solution to obtain a 0.100 M HNO3 solution?
Answer:
1. Percentage composition of: Na = 42%; P = 19.0%; O = 39%
2. Simplest formula of compound is PbO₂
3. (i) 2Cu(NO₃) ---> 2CuO + 2NO₂ + 3O₂
(ii) 2C₂H₆ + 7O₂ ---> 4CO₂ + 6H₂O
(iii) Mg₃N₂ + 6H₂O ---> 3Mg(OH)₂ + 2NH₃
4. 48 g of MG will react with 2 moles of Cl₂
5. 0.288 g of SO2 will be produced from the combustion of 0.331 g P₄S₃ in excess O₂
6. 12.8 g of nitric oxide can be produced from the reaction of 8.00 g NH₃ with 17.0 g O₂
7. The stock acid solution should be diluted to 6000 mL or 6.0 L
Explanation:
The full explanation is found in the attachments below
Metal atoms always form a cation of a single, specific charge.
a.) True, because metal atoms form ionic compounds of a known composition.
b.) False, because some metal atoms are known to have more than one possible positive charge.
c.) True, because nonmetal atoms always form anions of a single, specific charge.
d.) True, because metal atoms lose all of their valence electrons.
e.) False, because elements in different rows of the periodic table can form different cations.
Answer:
c.) true, because nonmetal atoms always form anions of a single , specific charge
An object is a regular, rectangular, solid with dimensions of 2 cm by 3cm by 2cm. It has a
mass of 24 g. Find its density.
Answer:
2
Explanation:
Density = mass/volume
m=24
v=2*3*2=12
24/12=2
Answer:
[tex]\boxed {\tt d= 2 \ g/cm^3}[/tex]
Explanation:
Density can be found using the following formula.
[tex]d=\frac{m}{v}[/tex]
where [tex]m[/tex] is the mass and [tex]v[/tex] is the volume.
We know the mass is 24 grams. We must find the volume.
Since it is a rectangle, the volume can be found using the following formula.
[tex]v=l*w*h[/tex]
The length is 2 centimeters, the width is 3 centimeters and the height is 2 centimeters.
[tex]v= 2 \ cm * 3 \ cm * 2\ cm[/tex]
[tex]v= 6 \ cm^2 * 2\ cm[/tex]
[tex]v= 12 \ cm^3[/tex]
Now we know the volume, and can substitute it into the density formula.
[tex]d=\frac{m}{v}[/tex]
[tex]m= 24 \ g\\v= 12 \ cm^3[/tex]
[tex]d=\frac{24 \ g}{12 \ cm^3}[/tex]
[tex]d= 2 \ g/cm^3[/tex]
The density is 2 grams per cubic centimeter.
I am timed please help!!
Answer:
it is a mixture
element are pure and compound are formed in a fixed ratio
Explanation:
Which of the reactions are spontaneous (favorable)?
A. 2Mg(s) + O2(g) rightarrow 2MgO (s) delta G = - 1137 kJ / mol
B. NH3(g) + HCl(g ) rightarrow NH4Cl(s) delta G = - 91.1 kJ / mol
C. AgCl(s) rightarrow Ag+ (aq) + Cl-[aq) delta G = 55.6 kJ / mol
D. 2H2(g) + O2(g) rightarrow 2H2O(g) delta G= 456 kJ / mol
E. C(s) + H2O(t) rightarrow CO(g) + H2(g) delta G = 90.8 kJ / mol
F. CH4(g) + 2O2(g) rightarrow CO2(g) + 2H2O(t) delta G = -820 kJ / mol
A. Reaction A.
B. Reaction B.
C. Reaction C.
D. Reaction D.
E. Reaction E.
F. Reaction F.
Answer: Reactions: A, B and F
Explanation: Gibbs Free Energy, symbol G, combines Enthalpy (sum of internal energy) and Entropy (measure of how much the energy of atoms and molecules become spread out in a process).
The change in free energy (ΔG) is the sum of enthalpy and the product of temperature and entropy of the system.
With free energy, it is possible to determine if a reaction is spontaneous, i.e., happens wthout external energy, or non-spontaneous.
If ΔG is negative, reaction is spontaneous. If ΔG is positive, reaction is non-spontaneous.
Analysing each ΔG of the reactions above, reactions A, B and F's Gibbs Free energy are negative, so these 3 are spontaneous.
What is the mass, in grams, of 1.33 mol of water, H2O?
Answer:
24.0g H2O
Explanation:
1.33 mol (18.016g/1 mol) = 24.0g H2O
Which wave has the greatest distance from trough to trough?
Answer:
C.C
Explanation:
Just took the test
A transverse wave is a motion in which all points on a wave oscillate along paths at right angles. Hence, option C is correct.
On a wave, what is the distance from trough to trough?The wavelength is the horizontal distance between two adjacent crests or troughs.
The longest distance a particle goes from rest is to the peak of a crest or the bottom of a trough in a transverse wave. The amplitude of a transverse wave is this distance.
Hence, option C is correct.
Learn more about wavelength here:
https://brainly.com/question/13533093
#SPJ2
Why does burned toast taste so bad? Is it a chemical or physical change?
Because things that are burnt have been changed into something else like moldy bread thats cooked.
It is chemical change because you cannot unburn something.
Answer:
It's a chemical change because I'm really good at answers
Explanation:
Which of the following is true concerning y? A) wdescribes the probability of finding an electron in space. B) ya describes the exact path of electron motion in an orbital. C) w? describes the electronic structure of the atom according to the Bohr model. D) w describes the exact volume of an atom. E) w2 describes the size of an atom.
Answer:
wdescribes the probability of finding an electron in space.
Explanation:
The quantum mechanical model of the atom assigns wave properties to the electron. This is in accordance with Heisenberg's uncertainty principle.
The probability of finding the electron in a given volume element is given as the square of the wave function while the wave function itself does not really have a physically significant meaning.
However, the wave function is a mathematical function that contains a detailed information about the behavior of an electron.
What is an example of a physical change?
A. having less ash than the paper that was burned to form it
B. ice forming and then melting back into water
C. rust having a different identity than the iron it forms on
D. the irreversible reaction of vinegar and baking soda
What one would you guys choose?
Answer:
B is correct answer
Explanation:
Answer:
B.
Explanation:
Draw the line-bond structure of oleic acid (cis-9-octadecenoic acid), CH3(CH2)7CH=CH(CH2)7COOH, at physiological pH. You do not need to draw hydrogen atoms attached to carbon atoms.
Answer:
Explanation:
Oleic acid originates from an unsaturated fatty acid with 18 carbon atoms and one double bond, which can be found in olive oil and many other vegetable and animal oils and fats. Its economic importance includes the production of soap making and cosmetics etc.
The line-bond structure of the given oleic acid in the question can be found in the attached below.
The line-bond structure of oleic acid is given in the image attached. The line-bond structure represents the number of carbon atoms.
Oleic acid:Oleic acid is an omega-9 fatty acid. It can be made by the body. It is also found in foods. Highest levels are found in olive oil and other edible oils. Oleic acid is most commonly used for preventing heart disease and reducing cholesterol. It is long chain of 18 Carbon atoms.
It is found in oils such as olive, palm, peanut, and sunflower.
Find more information about Oleic acid here:
brainly.com/question/26651977
Decaying plants and animals are important to an ecosystem because they
A.
cause disease in living organisms.
B.
reduce soil erosion.
C.
recycle oxygen to the air.
D.
return nutrients to the soil.
Answer:
The option D is correct answer.
Decaying pants and animals are important to the ecosystem as they return the nutrients to the soil.
What is an ecosystem?Ecosystem is defined as a system which consists of all living organisms and the physical components with which the living beings interact. The abiotic and biotic components are linked to each other through nutrient cycles and flow of energy.
Energy enters the system through the process of photosynthesis .Animals play an important role in transfer of energy as they feed on each other.As a result of this transfer of matter and energy takes place through the system .Living organisms also influence the quantity of biomass present.By decomposition of dead plants and animals by microbes nutrients are released back in to the soil.
Learn more about ecosystem,here:
https://brainly.com/question/19267717
#SPJ2
A ratio that compares the length and width of a garden is what type of model?
A. Physical
B. Conceptual
C. Computer
D. Mathematical
Answer:
D. Mathematical
Explanation:
calculate the density, in g/mL, of a liquid that has a mass of 0.165 g and a volume of 0.000295 l
Answer:
The answer is
0.56 g/mLExplanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\ [/tex]
From the question
mass of liquid = 0.165 g
Next we change the volume from L to mL using the conversion
1 L = 1000 mL
We have
If 1 L = 1000 mL
Then 0.000295 l = 1000 × 0.000295
volume = 0.295 mL
The density is
[tex]density = \frac{0.165}{0.295} \\ = 0.55932203...[/tex]
We have the final answer as
0.56 g/mLHope this helps you
How does the number of valence electrons in atoms of metalloids explain why metalloids are semiconductors? They have one or two valence electrons, so they cannot lose electrons easily. They have one or two valence electrons, so they can lose or gain electrons. They have three to six valence electrons, so they cannot lose electrons easily. They have three to six valence electrons, so they can lose or gain electrons.
Answer:
They have three to six valence electrons, so they can lose or gain electrons.
Explanation:
Here, we are required to identify how the number of Valence electrons on atoms of metalloids explain why metalloids are semiconductors.
This is because; They have three to six valence electrons, so they can lose or gain electronsMetalloids are elements in the periodic table which are characterized by the the presence of 3 to 6 Valence electrons.
Metalloids unlike Alkali and alkali earth metals (which have 1 and 2 Valence electrons and are highly electropositive) and halogens( with valency of 7 and are highly electronegative) have three to six valence electrons and are therefore able to lose or accept electrons.Ultimately, the presence of three to six Valence electrons and the ability to either lose or gain electrons is the criteria for their semiconductor character.
Read more:
https://brainly.com/question/2708814
Can someone please help me with this? :(
Answer:
Bo
Explanation:
Bo is not a element
Sample of carbonate rock is a mixture of CaCO3 and MgCO3. The rock is Analyzed in a laboratory and the results are recorded in the table above. Which columns in a table provide all the information necessary to determine the mole ratio of analyzed in a laboratory and the results are recorded in the table above. Which columns in a table provide all the information necessary to determine the mole ratio of Ca to Mg in the rock
Answer:
You need the mass of Mg and Ca in the sample and their molar masses
Explanation:
Its the only answer that made sense because using those 4, can give you their ration
The Columns in the table that provides the information necessary for the calculating the mole ratio of Ca to Mg are columns ; 3, 4, 6, and 7
Although some data related to your question is missing attached below is the missing data
Determining the mole ratio of Ca to Mg
Ca : Mg
mass of Ca / molar mass : mass of Mg / Molar mass
( 36.1 / 40.1 ) : ( 2.4 / 24.3 )
9.14 : 1
∴ The mole ratio of Mg to Ca
≈ 1 : 9
Where: Column 3 = Mass of Mg in the sample ( g )
Column 4 = mass of Ca in the sample ( g )
Column 6 = Molar mass of Mg ( g/mol )
Column 7 = molar mass of Ca ( g/mol )
Hence the Mole ratio of Mg to Ca = 1 : 9
learn more : https://brainly.com/question/15371665
A bird flies 3.7 meters in 46 seconds, what is its speed?
v=
d=
t=
Answer:
speed = 3.7/46 = 0.080m/s
d= 3.7m
t= 46s
Explanation:
The particles of a gas inside a balloon are experiencing an increase in their average kinetic energy and the number of collisions with the wall of the balloon. What is the most likely outcome? higher gas pressure inside the balloon higher air pressure outside the balloon a decrease in gas temperature inside the balloon a large increase in air temperature outside the balloon
The higher Gas pressure inside the balloon. Hence, option A is correct.
How is kinetic energy related to temperature?In a molecule, the kinetic energy existing is "directly proportional" to the temperature of the molecule. If one of the values increases, then the other value also increases and vice-versa.
The higher Gas pressure inside the balloon. As the number of collisions with the wall of the balloon increases, the pressure inside increases.
Hence, option A is correct.
Learn more about kinetic energy here:
https://brainly.com/question/12669551
#SPJ5
How many cm are in 29.7km?
Answer:
there are 2970000cm in 29.7km
Explanation:
6.300x10-5 – 7.200x10-3
Answer:
-17
Explanation:
6300/1000×10-5-7200/1000×10-3
63000/1000-5-72000/1000-3
63-5-72-3
-17
the coefficient is -7.137 but i’m not sure what the exponent is, i’m sorry :/
Where did I go wrong? I know the 2.58 is the right answer but where did I go wrong in my work? Please help!!
Answer: See below
Explanation:
In this problem, conversion factors are very important. In the second conversion, you wrote 1 kg=0.001 g. This is incorrect. It should be 1 kg=1000g. Otherwise, the rest is correct. Make sure to have correct conversions. The answer will be correct.
Complete hydrolysis of a hexapeptide gives 2 Gly, Leu, Phe, Pro, and Tyr. Reaction of the peptide with phenylisothiocyanate gave the phenylthiohydantoin of Pro. Partial hydrolysis of the peptide gave the following fragments: Phe-Gly-Tyr, Gly-Phe-Gly, Pro-Leu-Gly, Leu-Gly-Phe. What is the structure of the peptide
Answer:
The complete sequence : Pro-Leu-Gly-Phe-Gly-Tyr
Explanation:
For the formation of phenylisothiocyanate, the four peptide sequences overlap common residue to get the the complete sequence of the hexapeptide as shown in the diagram attached below
Attached below is the structure of the peptide
What determines the reactivity of an akali metal?
Answer:
The number of valence electrons determines an element's reactivity, or how likely the element is to react with other elements.
Explanation:
i am timed please help
Answer:
mixture
Explanation:
there was leftover components meaning there was something mixed into the liquid
Is matter smooth and continuous?
Answer:
YES,Explanation:
Matter is smooth and continuous. ... A liquid has a definite volume; but it has no definite shape.An element has a mass number of 9 and 5 neutrons. What element is it?
Answer:
Fluorine
Fluorine is the element in question, as its atomic number is 9 . You would name this particular isotope using the mass number. It would be called fluorine-19.
Explanation:
Answer:
Fluorine
Fluorine is the element in question, as its atomic number is 9 . You would name this particular isotope using the mass number. It would be called fluorine-19.
at what height is an object that has a mass of 16kg, if it’s gravitational potential energy is 7500J?
Answer:
46.875
Explanation:
P.E=MGH
7500=16*10*h
7500=160h
h=7500/160
h=46.875
Solve: (6.825 x 10-3) (1.2 x 10-8)
Choose the answer with the correct number of significant figures.
a 8.2 x 10-11
b 0.081 x 10-8
C 8.01 x 1011
d None of the above
Answer: a.) 8.2 x 10^-11
Explanation:
12.A piece of magnesium is in the shape of a cylinder with a height of 5.62 cm
and a diameter of 1.34 cm. If the magnesium sample has a mass of 14.1 g, what
is the density of the sample?
Answer:
Density, d = 1.779 g/cm³
Explanation:
The density of a material is given by its mass per unit volume.
Here, height of a piece of magnesium cylinder, h = 5.62 cm
Its diameter, d = 1.34 cm
Radius = 0.67 cm
Volume of he cylinder,
[tex]V=\pi r^2 h\\\\\text{Putting the value of r and h, we get :}\\\\V=(\pi \times (0.67)^2\times 5.62)\ cm^3[/tex]
[tex]d=\dfrac{m}{V}\\\\d=\dfrac{14.1\ g}{(\pi \times (0.67)^2\times 5.62)\ cm^3}\\\\d=1.779\ g/cm^3[/tex]
So, the density of the sample is 1.779 g/cm³.