Answer:
Molecular formula = C₄H₆O₂
Explanation:
Given data:
Empirical formula of butanedion = C₂H₃O
Molar mass of butanedion = 86.09 g/mol
Molecular formula butanedion = ?
Solution:
Formula:
Molecular formula = n(empirical formula)
n = molar mass of compound / empirical formula mass
empirical formula mass = 2×12 +1.008×3 +1×16 = 43.024
n = 86.09 / 43.024
n = 2
Molecular formula = n (empirical formula)
Molecular formula = 2 (C₂H₃O)
Molecular formula = C₄H₆O₂
19. Who was the first female astronomer
A.Aristotle
B.En Hedu’Anna
C.Archimedes
D.Plato
Answer: A.En Hedu'Anna
Answer:
En Hedu’Anna!
Explanation:
Why is hydrogen peroxide sold in opaque plastic bottles?
it's not a very stable compound
12. A 100.00-gram sample of naturally occurring boron
contains 19.78 grams of boron-10 (atomic mass =
10.01 atomic mass units) and 80.22 grams of
boron-11 (atomic mass = 11.01 atomic mass units).
Which numerical setup can be used to determine the
atomic mass of naturally occurring boron?
A) (0.1978)(10.01) + (0.8022)(11.01)
B) (0.8022)(10.01) + (0.1978)(11.01)
C) (0.1978)(10.01)/(0.8022)(11.01)
D) (0.8022)(10.01)/(0.1978)(11.01)
It’s A) (0.1978)(10.01) + (0.8022)(11.01)
Relative and average atomic mass both describe properties of an element related to its different isotopes. Out of these two Relative atomic mas is more accurate. Therefore option A is correct option.
What is mass?Mass defines the quantity of a substance. It is measured in gram or kilogram. Average mass is the mass of atoms of an element that are isotopes. It can be calculated by multiplying mass of a isotope to natural abundance of that isotope.
Mathematically,
average atomic mass= ∑(relative abundance x mass of isotope)
average atomic mass boron= (relative abundance boron-10 x mass of isotope boron-10)+(relative abundance boron-11 x mass of isotope boron-11 )
average atomic mass boron=(0.1978)(10.01) + (0.8022)(11.01)
Therefore option A is correct option.
To learn more about mass, here:
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which of the following molecules has only two non binding pairs (long pairs) of electrons in its lewis structure?
a)O2
b)CH4
c)NH3
d)H2s
Explanation:
NH₃ has only two non-binding pairs (lone pairs) of e⁻ in it's Lewis structure.
••
H—N—H
|
H
Therefore,
C is correct. ✔
It is found that after 24!hours 1/8 of the mass of a sample of a radio-active isotope remains What is the half-life of this isotope?
Answer:7.72 years
Nuclear half-life expresses the time required for half of a sample to undergo radioactive decay.
Explanation:
0.01 = 67.0 ×[tex](\frac{1}{2}) ^{\frac{98.0} {1/2 } }[/tex] [tex]\frac{0.01}{67.0}[/tex] = 0.000149=[tex](\frac{1}{2}) ^{\frac{98.0} {1/2 } }[/tex]
[tex]^{\frac{98.0} {1/2 } }[/tex] =log[tex]_{0.5}[/tex] (0.000149)=12.7
[tex]^{\frac{98.0} {1/2 } }[/tex]=7.72 years
Hope this helps have a great day/afternoon :)
The distinctive odor of vinegar is due to acetic acid, HC₂H₃O₂, which reacts with sodium hydroxide. If a 3.45 mL sample of vinegar needs 42.5 mL of 0.115 M NaOH to be neutralized, how many grams of acetic acid are in a 1.00 L bottle of this vinegar?
Answer:
Explanation:
CH₃COOH + NaOH = CH₃COONa + H₂O .
42.5 mL of .115 M of NaOH will contain .0425 x .115 moles of NaOH
= 48.875 x 10⁻⁴ moles NaOH
It will react with same number of moles of acetic acid
So number of moles of acetic acid in 3.45 mL = 48.875 x 10⁻⁴
number of moles of acetic acid in 1000 mL = 48.875 x 10⁻⁴ x 10³ / 3.45 moles
= 1.4167 moles
= 1.4167 x 60 gram
= 85 grams .
So 85 grams of acetic acid will be contained in one litre of acetic acid.
Why the noble gases are found in small amounts in the earth's atmosphere?
Answer:
They have completely filled outermost shell
Explanation:
The noble gases are the rarest and occur in trace amounts in the atmosphere because they have completely filled outermost and this makes them unreactive with other elements.
Elements become abundant as they combine with other species to form compounds.
Noble gases on the other hand have a high level of stability and do not readily combine with other species.
Some of these gases are :
Helium
Neon
Argon
Krypton
Xenon
Radon
They have very high ionization energy and very low electron affinity and so will not readily react.
what acts as a buffer for seawater ?
Answer:
The bicarbonate and carbonate ions.
Explanation:
Probably not he answer your looking for though. So, CO2.
What type of reaction is the equation 2NaCl → 2Na +Cl2?
Answer:
Synthesis reaction
Explanation:
This is a synthesis reaction. When you combine sodium metal (Na) with chlorine gas (Cl), you form sodium chloride or kosher salt (NaCl).
Hope this explanation helps!
Is the freezing point of this 5??
Please correct my mistake if it isn't.
Answer:
yes
Explanation:
Answer:
yes
Explanation:
you're smart have a nice evening
Using the em figure what color is the wavelength 436 nm
Answer:
Blue
Explanation:
Between Na and Na+ which has larger size
Answer:
Na+ is smaller than Na because, it has given away one electron because of which the electron shielding gets stronger due to more protons and less electrons. Whereas, Cl- is larger than Cl because it has gained an extra electron and so, the no.07/12/2010
Explanation:
PLEASE ANSWER
A train travels 200 miles at an average speed of 50 miles per hour. How long does it take the train to travel this distance?
In which of the following physical states are the particles in constant motion?
1. Solid
II. Liquid
III. Gas (Vapor)
I and Ill only
O I. II and III
Oil and ill only
Ill only
Answer:
cgeh
Explanation:salamat
Snakes and similar animals are members of a group called reptiles.
How do reptiles differ from other animals?
Answer:
They have skin covered with scales.
How many grams are in 1.98 x 1024 formula units of NaCl?
Answer:
There are 2027.52 formula units of NaCl
Explanation:
plz mark me brainlest
Which particle changes to create a positive or negative ion of an atom?
A.proton
B. neutron
C. electron
Answer:
it is alkali
Explanation:
hope it helps you
6. How is energy transferred to the earth?I
Answer:
Energy is transferred between the earths surface and atmosphere.Energy move place to place
why is diamond said to be hard
Answer: Diamond is said to be the hardest element because it is unbreakable by humans. These diamonds are mined, and they are very hard. A miner knows when they have found diamond when they feel something super hard.
Hope this helps you!
Explain what intermolecular forces are, and how they are easily overcome.
Explanation:
Intermolecular forces are forces that exist between two or more molecules and they can be overcome at high temperatures.
PLEASE explain your answer!!!!
Answer:
Explanation: confusing
The capability of a substance to be stretched into thin wires without breaking is known as —
A malleability
B conductivity
C luster
D ductility
Answer:
The answer is D, ductility
Explanation:
The definition of ductile is "(of a metal) able to be drawn out into a thin wire."
Which particle changes to create a new element?
A.proton
B.neutron
C.electron
Answer: A
Explanation:
Wear lightweight clothes in the_____. not sun or summer and is it heat
Answer:
there was too much heat
Explanation:
2) A student was working on an investigation to measure the relative activity
of an enzyme at various pH values. He collected the following data:
pH 2, enzyme activity 10; pH 8, enzyme activity 50;
pH 12, enzyme activity 10; pH 4, enzyme activity 20;
pH 6, enzyme activity 40; pH 10, enzyme activity 40
Answer:
THE LAST ONE
Explanation:
Is the following an element, compound, homogeneous mixture, or heterogeneous mixture?
Coca-cola
Answer:
CO2 is classified as a compound
Explanation:
Explain why you cannot use a pump like the one at the right to
lift water up to the 3rd floor of an apartment building.
Answer:
can you aks it more clerlry
Explanation:
what is the electron configuration for gallium
Answer:
[Ar] 3d^104s^24p^1
6. What is one way a star with much more mass than the sun can end up?
white dwarf
red giant
neutron star
red dwarf
Answer:
neutron star
Explanation:
A massive star (More massive than the star) will undergo a supernova explosion. If the remnant of the explosion is 1.4 to about 3 times as massive as our Sun, it will become a neutron star. The core of a massive star that has more than roughly 3 times the mass of our Sun after the explosion will do something quite different
Please answer correctly !!!!!!!!!!!!!!!!! Will mark brainliest !!!!!!!!!!!!!!!! And explain please !!!!!!!!!!!!
Hope this is your answer i wasn't able to see he full question so i am not sure