Answer:
15 atoms left after 3 half lives
Explanation:
17145 y / 5715 y/halflife = 3 half lives
(1/2)^3 = 1/8 of original is left
1/8 ( 120 atoms) = 15 atoms left
How many molecules are in 2.0 moles?
Answer:
12 or 1.24e
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A molecule that is either cycloheptane or cycloheptene is treated with bromine and the sample immediately absorbs the red bromine color—which compound is present?
The compound that is most likely present when treated with bromine and the sample absorbs the red bromine color is ; Cycloheptene
What is cyclohepteneCycloheptene is an unsaturated colorless oily liquid which is insoluble in water it absorbs Bromine when used in performing unsaturation test due it unsaturated nature.
The red bromine color will be absorbed when used to treat Cycloheptene but will not be absorbed when used to treat cycloheptane due to its saturated nature.
Hence we can conclude that the compound that is present is Cycloheptene.
Learn more about Unsaturation : brainly.com/question/561845
Thermal energy always moves from a greater energy level to a lesser energy level
Theory or law?
Give an explanation please
Answer:
[tex]\fbox{Law -Based \: on \: laws \: of \: thermodynamic}[/tex]
Explanation:
At constant pressure Thermal energy always moves from a greater energy level to a lesser energy level, laws of thermodynamics prove that.
Nature always likes to attain equilibrium either it's movement of heat energy or flow of water from higher region to lower region. The first and second law of thermodynamics are profe of that, the first law says that the total energy of universe is Constant. Energy can not be destroyed it always changes from one form to another, by work and heat. The second law explains why thermal energy moves from a greater energy level to a lesser energy level, it deals with the change in entropy of a system and surrounding and states heat flows from hot environment to cold environment.
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what happens when ethanol reacts with alkaline potassium permanganate?
Answer:When ethanol is oxidised with alkaline potassium permanganate (alkaline KMnO 4) or acidified potassium dichromate (acidified K 2 Cr 2 O 7), ethanoic acid is formed. Alkaline potassium permanganate and acidified potassium dichromate are strong oxidising agents, as they provide oxygen for oxidising other substances in the reaction
Explanation:
particles in the liquid state have _________ IM attractive forces than in the gas state
Answer:
Particles in the liquid state have greater IM attractive forces than in the gas state.
Which of the following sets of quantum numbers (n, l, ml, ms) cannot occur within an atom of gallium?
A. 4, 0, 0, ½
b. 4, 2, 1, ½
c. 4, 1, 1, ½
d. 4, 1, 2, ½
e. 4, 3,1, 1/2
The following sets of quantum numbers ( n, I, ml, ms ) that cannot occur within an atom of gallium are :
4, 2, 1, ½ ( B ) 4, 1, 2, ½ ( D ) 4, 3,1, 1/2 ( E )Determine the sets of quantum numbers that cannot occur within an atom of gallium
Given that
Ga ( 31 ) = 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p¹
[ 4r ] 3d¹⁰ 4s²4p¹
where : n = principal quantum numbers, l = azimuthal quantum numbers, ml = magnetic quantum numbers, ms = spin quantum numbers.
For option B
Given that 4d shell is absent for Gallium the set cannot occur within the atom of Gallium
For Option D and E
All quantum number cannot occur here because the value of l = 2 for option D while for option E the value of l = 3
Hence we can conclude that sets of quantum numbers ( n, I, ml, ms ) that cannot occur within an atom of gallium are as listed above.
Learn more about quantum numbers : https://brainly.com/question/2292596
How many molecules of methane (CH4) do you need to burn in order to get 9.03 x 1023
molecules of carbon dioxide (CO2)? Avogadro's number is 6.02 x 1023 molecules/mol.
CH4 + O2 - CO2 + 2H2O
Answer:
9.03*10^23 molecules CH4
Explanation:
In the equation CH4 + O2 -> CO2 + 2H2O, the molar ratio of CH4 to CO2 is 1:1. It takes 1 mole of CH4 burned to form 1 mole of CO2. If we convert molecules to moles, we do 9.03 x 10^23 divided by 6.02 x 10^23 = 1.5 moles of CO2. Since we know the ratio is 1:1, that meant it would take 1.5 moles of CH4 burned to make that much CO2. So we convert our 1.5 moles of CH4 into molecules by multiplying 1.5 * 6.02 x 10^23 which equals 9.03*10^23 molecules CH4.
21.10g of NaOH and Ba3(OH)2 mixture is dissolved water to prepare 1.0dm³ Solution. To neutralize 25.OO mL of this solution needs 0.5 moldm-³ HCl 15.00mL. calculate the percentage of NaOH by mass in the mixture.
From the equation of te reaction, we know that the mass percent of NaOH in the mixture is 1.4%.
What is neutralization?Neutralization is a reaction that occurs between an acid and a base to yield salt and water only.
In tis case, the reaction of the NaOH and HCl occurs as follows; NaOH + HCl ----> NaCl + H2O
Number of moles of HCl reacted = 15/1000 * 0.5 moldm-³ = 0.0075 moles
Since the reaction is 1:1, 0.0075 moles of NaOH reacted.
Mass of NaOH = 0.0075 moles of NaOH * 40 g/mol = 0.3 g
Percent of NaOH = 0.3 g/21.10g * 100/1 = 1.4%
Learn more about percent concentration: https://brainly.com/question/202460
What are ways in which the body is gain and loses soduim?
Answer:
You gain sodium basically through the food you eat and lose it basically by excretion through urine,sweat
