Rafiq should expose one piece under the lamp for 10 days while keeping the other in the darkness.
What are the elements in this experiment?In this experiment, it is essential to have a control group and an experimental group.
Control group: This is the population that does not receive a "treatment" or in this case the piece of fabric that is not exposed to light. It is essential to have this element because it works as a reference.Experimental group: This is the population that receives a special "treatment" or in this case the piece of fabric that must be exposed to light to test if there is a color change.Which experiment design is the best for Rafiq?Based on the previous ideas, the best for him is to keep one piece of clothing in the darkness (control group), while exposing the other to the light of the lamp (experimental group).
In this way, he can determine if there is a real change of color by comparing both pieces after 10 days.
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What is the molecular formula of the molecule that has an empirical formula of CH2O and a molar mass of 120.12 g/mol
Answer:
C4H8O4
Explanation:
Let (CH20)x
C=1*12.01=12.01 (12.01, 1.01, 16.00 Avg mass of elements)
H=2*1.01=2.01
O=1*16.00=16.00
12.01 + 2.01 + 16.00 = 30.03
120.12/30,03=4
==> (CH2O)4 = C4H8O4
The molecular formula of the molecule that has an empirical formula of [tex]CH_2O[/tex] is equal to [tex]C_4H_8O_4[/tex].
Given the following data:
Empirical formula = [tex]CH_2O[/tex]Molar mass = 120.12 g/mol.Scientific data:
Molar mass of oxygen = 16 g/mol.Molar mass of hydrogen = 1 g/mol.Molar mass of carbon = 12 g/mol.To determine the molecular formula of the molecule that has an empirical formula of [tex]CH_2O[/tex]:
First of all, we would find the molar mass of [tex]CH_2O[/tex]:
[tex]CH_2O =12 +(1\times2)+16\\\\CH_2O =30\;g/mol[/tex]
For molecular formula:
[tex](CH_2O)n = 120.12\\\\30n = 120.12\\\\n=\frac{120.12}{30}[/tex]
n = 4.0
[tex](CH_2O)_4 = C_4H_8O_4[/tex]
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Someone help with this ions and isotopes worksheet?
Isotopes are atoms of the same element that have different numbers of neutrons. Protons are positively-charged particles found in the nucleus of an atom.
Electrons are negatively-charged particles found in the outer shell of an atom. The charge on an element is determined by the number of protons and electrons present in the atom.
a.) Li+: number of protons = 3
Number of electrons = 2
charge of Li+ = +1
b.) Be2+: number of protons = 4
Number of electrons = 2
charge of Be2+ = 2+
c.) C4+: number of protons = 8
Number of electrons = 4
charge of C4+ = 4+
d.) O2-: number of protons = 8
Number of electrons = 10
charge of O2- = -2
e.) N3-: number of protons = 7
Number of electrons = 10
charge of N3- = -3
f.) C4- : number of protons = 4
Number of electrons = 4
charge of C4- = -4
g.) 14C6: The mass number = 14
Atomic number = 6
Number of neutrons = 8
h.) 18O8: The mass number = 18
Atomic number = 8
Number of neutrons = 10
i.) 19F9: The mass number = 19
Atomic number = 9
Number of neutrons = 10
j.) 40Ca20: The mass number =40
Atomic number = 20
Number of neutrons = 20
k.) 37Cl17: The mass number = 37
Atomic number = 17
Number of neutrons = 20
l.) 238U92: The mass number = 238
Atomic number = 92
Number of neutrons = 146
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Answer correctly please !!!!!!!!!!!!!!! Will mark brainliest !!!!!!!!!!!!!!!!!
A student uses a magnet to move a 0.25kg metal ball. The magnet exerts a force of 5N on the ball. What is the acceleration of the ball when it begins to move ?
Answer:
20 m/s²Explanation:
The acceleration of an object given it's mass and the force acting on it can be found by using the formula
[tex]a = \frac{f}{m} \\ [/tex]
f is the force
m is the mass
From the question we have
[tex]a = \frac{5}{0.25} \\ [/tex]
We have the final answer as
20 m/s²Hope this helps you
Choose the correct one plz!
Answer:
b
Explanation:
Answer:
13 N to the right
Explanation:
how can one separate and collect the solvent from a salt solution
Question 5 (2 points)
Which of the following has a higher boiling point, CO2 or Co? Explain.
Answer:
CO2 has higher boiling point as compared to CO
Explanation:
Because CO is linear molecule anf zero dipole moment while CO2 is non linear and it has dipole moment
Use the periodic table to identify the number of valence electrons available for bonding for each of the following elements.
Answer: Edgy, 2020
Explanation: <3
Answer:
refer to picture below :)
Explanation:
giving brainliest if correct!! please help someone out?
Answer:
protons: 36
neutrons:48
electrons:36
Explanation:
the number of protons in an element is = to the atomic # (36)
the number of neutrons is the atomic mass - atomic # (84-36=48)
In a neutral charged element the # of protons = # of electrons
Divergent tectonic plate boundaries most commonly form one: A non-volcanic islands. B ocean trenches C continental mountains D ocean ridges
Answer:
D. ocean ridges
Explanation:
Answer:
I think A
Explanation:
Most volcanoes form at the boundaries of Earth's tectonic plates. ... The two types of plate boundaries that are most likely to produce volcanic activity are divergent plate boundaries and convergent plate boundaries
Are scientist improving the plant or corrupting it
Answer:
46 percent of trees have been cut down.
Scienctists helps plants, but humans do destroy a lot of plants.
Scientists - helps increase plant growth.
Woodchoppers - helps decrease plant growth.
i will give braniliest
During World War II, the Nazi government in Germany imprisoned and murdered millions of Jews. This is known as the _____.
A.Fascism
B.Holocaust
C.Nationalism
D.Great Depression
Answer:
B
Explanation:
how does the octet rule predict the stability or reactivity of atoms.
Answer:
Explanation:
The octet rule allows chemists to predict the placement of electrons around the nucleus (electron orbitals), the identification of electrons added or lost during chemical reactions and the chemical reactivity of atoms based upon their particular electron configuration.
two differences between atom and molecules
Answer:
Molecules are made of atoms. atoms are smaller. molecules have no electrons, atoms do.
Answer:
well one of the begins with and A while the other one begins with a M, joking so the difference between an atom and a molecules is that, An atom is the smallest unit of matter that retains all of the chemical properties of an element. while Molecules can be described as the smallest particle of an element or a compound, which is capable to exist independently and shows all the properties of the respective substance. Hope this helps :)
Explanation:
What is the name given to the group 0 elements
Answer:
the noble gases
elements have the same number of what when you move from the left of the periodic table to the right?
How much force is required to accelerate an 8-kg wagon at a rate of 15 m/s
Answer:
120 NExplanation:
The force acting on an object given it's mass and acceleration can be found by using the formula
force = mass × acceleration
From the question we have
force = 8 × 15
We have the final answer as
120 NHope this helps you
How are a mole and a dozen similar?
Answer:
Each names a given number of objects.
Explanation:
According to the text, which amino acid(s) contains a side chain..
a. in which molecules form covalent disulfide bridges with each other?
b. that is hydrophobic?
c. that forms hydrogen bonds?
d. that is basic?
Answer:
(b) that is hydrophobic
Explanation:
e.g, alanine
Cause, Alanine possess hydrophobic side chain and the most appropriate answer is (d) part......
Alanine is an aliphatic amino acid, because the side-chain connected to the α-carbon atom is a methyl group (-CH3), alanine is the simplest α-amino acid after glycine. The methyl side-chain of alanine is non-reactive and is therefore hardly ever directly involved in protein function..
Hope it will help you☺☺☺☺☺
Answer:
(b) that is hydrophobic
Explanation:
e.g, alanine
Cause, Alanine possess hydrophobic side chain and the most appropriate answer is (d) part......
Alanine is an aliphatic amino acid, because the side-chain connected to the a-carbon atom is a methyl group (-CH3), alanine is the simplest a-amino acid after glycine. The methyl side-chain of alanine is non-reactive and is therefore hardly ever directly involved in protein function...
Hope it helps....
Worth 50 points. Please answer correctly
Answer:
question 2 is false
Explanation:
6 is D
which equation is derived from the combined gas law?
Answer:
The correct answer is V1/T1=V2/T2.
Explanation:
Just took the test
Answer:
Its A on edge :)
Explanation:
Can someone please help me with this???
Answer:
1)
Hg
80 protons, 80 electrons, 121 neutrons
2)
Mo
42 protons, 42 electrons, 54 neutrons
3)
Symbol is Cu, Mass is 64, 29 Protons
4)
C
Atomic number is 6, 6 protons, 6 electrons, 6 neutrons
5)
Symbol is P, 15 protons, 15 electrons, 16 neutrons
6)
Pb
Atomic number is 82, 82 electrons, 125 neutrons
7)
Na
Mass is 23, 11 protons, 11 electrons.
Hopefully this helps!
A hydrate of CoCl2 has a mass of 15.80 g before heating. After heating the mass of the anhydrous compound is found to be 9.32 g explain how you would determine the formula of the hydrate and then write out the full name of the hydrate
Explanation:
Molar mass of Cobalt (II) chloride = 129.8g/mol
Moles of CoCl2 = 9.32/129.8 = 0.0718mol
Mass of H2O lost after heating = 15.80 - 9.32 = 6.48g
Moles of H2O = 6.48/18 = 0.36mol
Mole ratio of CoCl2 : H20
= 0.0718mol : 0.36mol
= 1 : 5
Hence the formula is CoCl2 . 5H2O, which is Copper (II) chloride pentahydrate.
Based on table N of the reference tables what is the number of hours required for 42k (potassium -42) to undergo three half-life periods
The number of hours required : 37.2 hours
Further explanationGiven
⁴²K (potassium -42)
Required
The number of hours
Solution
The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.
Usually, radioactive elements have an unstable atomic nucleus.
Based on Table N(attached), the half-life for ⁴²K is 12.4 hours, which means half of a sample of ⁴²K will decay in 12.4 hours
For three half-life periods :
[tex]\tt 3\times 12.4=37.2~hours[/tex]
How many oxygen atoms are there in
Fe203?
Answer:3 oxygen atoms.
Explanation: Each formula unit of Fe2O3 contains 2 atoms of iron and 3 atoms of oxygen (technically they are ions, but that doesn't matter).
Choose all the answers that apply.
Argon (Ar) is in group 18. Argon _____.
forms a salt when combined with a metal
has 18 electron shells
has properties similar to other elements in group 18
does not react readily with other elements
is part of the noble gas group
!(more than one answer)!
Answer: has properties similar to other elements in group 18, does not react readily with other elements, is part of the noble gas group
Explanation: I’ve done on edg before
Consider X + Z -> ?
Assuming the following:
The product is an ionic compound.
Element X has 2 valence electrons
Elements Z has 6 valence electrons
Which general formula would be created?
A)ZX
B)Z^2x
C)XZ
D)X2^Z
Answer:
C
Explanation:
Element Z acquires two electrons from element X for stability
first to answer correctly gets brainleist
Which lunar phase will occur approximately 7 days after a first quarter moon?
a
New moon
b
Full moon
c
Waxing crescent
d
Waning crescent
Answer:
c. Waxing crescent
- I hope this helps have a great night
The speed of light is 300,000,000 m/s. What is the frequency of microwaves with a wavelength of 0.01 meter?
Answer:
30,000,000,000 Hz
Explanation:
I searched it up and got 3 x 10^10 and thats 30000000000
What is the molar mass of phosphorus pentachloride and uranium hexafluoride?
Answer:
PCl₅ = 208.22g/mol. UF₆ = 352.03g/mol.
Explanation:
Find the atomic mass of each element–and if there's a subscript (you multiply the atomic mass by that much). P= 30.97g, Cl= 35.45g; 30.97+35.45(5) = 208.22g [same idea with UF₆]