Explanation:
moles= number of particle or atom / 6.02×10^23
so
[tex] \frac{1.1 \times {10}^{20 } }{6.02 \times {10}^{23} } [/tex]
gives u 1.83×10^-4 moles
hope it make sense :)
Answer:
1.7 * 10^-4 moles
Explanation:
According to Avogadro, one mole of a substance contains 6.02 * 10^23 number of atoms, molecules, ions etc.
Hence;
1 mole of Na contains 6.02 * 10^23 atoms
x moles of Na contains 1.0x10^20 atoms
x = 1.0x10^20 * 1/6.02 * 10^23
x = 1.7 * 10^-4 moles
PLEASE QUICKLY. I'll give BRAINLIEST. A sample contains 25% parent isotope and 75% daughter isotopes. If the half-life of the parent isotope is 72 years, how old is the sample?
144 years old
216 years old
288 years old
360 years old
From the calculations and the principles of radioactivity, the age of the parent isotope is 144 years
What is radioactivity?The term radioactivity has to do with the spontaneous decay of a substance.
We know that we have about 25% parent isotope still remaining hence;
[tex]0.693/t1/2 =2.303/t log No/N\\When N =0.25 No and t1/2 = 72 years\\0.693/72 =2.303/t log No/0.25No\\0.0096 = 2.303/t *0.60206\\0.0096 = 1.3865/t\\t = 1.3865/0.0096\\t =144 years[/tex]
Learn more about radioisotope:https://brainly.com/question/13076859
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Answer:
A. 144 years old
Explanation:
A gas has an initial pressure of 120 kPa, a volume of 23 liters, and a temperature of 20°C. If the pressure is raised to 150 kPa the new volume is 17 liters, what is the new temperature of the gas? *
A.100 K
B.0.003 K
C.270.7 K
D.18.4 K
Examine the food chain below: In this specific food chain, the _______ eats plants for food. A. caterpillar B. sunshine C. bobcat D. leaf
the tissue which continually forms new cells in plants
Answer:
Meristematic Tissues. Tissues where cells are constantly dividing are called meristems or meristematic tissues. These regions produce new cells.
Explanation:
thank me later
when chlorine gas is passed through potassium Bromide solution Potassium Chloride and bromine are formed which is a more reactive non metal bromine or chlorine
[tex] \boxed{\boxed{\huge{ \mathbf{ \underline{ Answer} \: \: ✓ }}}}[/tex]
In a displacement reaction, more reactive element displaces less reactive element from its compound and from the above reaction we observed that, Chlorine displaces bromine from its compound (KBr) to form Potassium chloride (KCl), therefore Chlorine is more reactive non - metal.
The equation for above reaction is :
[tex] \large\boxed {\mathrm{2KBr + Cl_2 \rightarrow 2KCl + Br_2}}[/tex]
_____________________________
[tex]\mathrm{ ☠ \: TeeNForeveR \:☠ }[/tex]
Pls answer this Il give brainiest question in picture ty
Answer:
c
Explanation:
troposphere is the answer
I’d appreciate the help! :)
Here is the reaction:
3 NO2 (g) + H2O (l) = 2HNO3 (l) + NO (g)
Answer: 300g
Explanation:
first we write the given values on top
224L. x
3 NO2 (g) + H2O (l) = 2HNO3 (l) + NO (g)
22.4L 30g
then we form a formula
224L/22.4L= x/30g
224*30/22.4
6720/22.4= 300g
PLEASE HELP!
The specific heat of octane, C8H18(l), is 2.22 J/(g⋅K).
How much heat is needed to raise the temperature of 76.0 g of octane from 10.6 ∘C to 26.0 ∘C?
Express your answer in joules to three significant figures.
Answer:
Q = 2.60 • [tex]10^{3}[/tex] J
Explanation:
Our specific heat capacity equation is:
Q = mC∆T
Q is the energy in joules.
m is the mass of the substance.
∆T is the temperature chance.
Let's plug in what we know.
We have 76.0 g of octaneThe specific heat capacity of octane is 2.22 J/(g•K)The temperature increases from 10.6º to 26.0º (a 15.4º increase)Q = 76.0(2.22)(15.4)
Multiply.
Q = 2598.288
We want three significant figures.
Q = 2.60 • [tex]10^{3}[/tex]
or
Q = 2590 J
Hope this helps!
Answer:6,985.008
Explanation:
so the hear formula is mass times specific heat times change in temperature (kelvin) so what i did was got the change in temperature (41.4 K) and multiplied that times 2.22 J/(g•K)and multiplied that by 76 grams of Octane to get the Answer (not in scientific notation)
Please help me I will give brainliest to the first correct answer
Answer:
OPTIC B) HEPT-HOPE IT IS HELPFUL
When 1 mol of methane is burned at constant pressure, −890 kJ/mol of energy is released as heat. If a 1.67 g sample of methane is burned at constant pressure, what will be the value of ∆H
Answer:
[tex]\Delta H=-92.7kJ[/tex]
Explanation:
Hello there!
In this case, according to the given information, we can infer that 890 kJ of energy are released when 1 mole of methane is burned; however, to find the total heat when 1.67 grams are burned, we first need to calculate the moles in this mass of methane:
[tex]1.67gCH_4*\frac{1molCH_4}{16.04gCH_4}=0.104molCH_4[/tex]
And thus, for calculating the resulting ∆H, we proceed as follows:
[tex]\Delta H=-890kJ/mol*0.104mol\\\\\Delta H=-92.7kJ[/tex]
Regards!
why metal in the middle of metal activity series can't be obtained by heating ors in air
Answer:
See Explanation
Explanation:
The way by which a metal is obtained from its ore is determined by the chemical reactivity of the metal.
Metals that are highly reactive are chiefly obtained by electrolysis of the metal salt. These metals are found high up in the metal activity series.
Metals that are at the middle of the series are moderately reactive and are obtained by electrolysis or by reduction since they still form ionic salts.
Metals that are far lower in the series can only be obtained by heating them in air because they are mostly unreactive.
Hence, moderately reactive metals at the middle of the series are not obtained by roasting in air.
is how much a material opposes electric current.
*
insulator
conductor
resistance
short circuit
Answer:
Resistance
Explanation:
Resistance is the measure of the opposition of current in a circuit.
112 g of aluminum carbide react with 174 g water to produce methane and aluminum hydroxide in the reaction shown below.
2 Al4C3(s) + 12 H2O(l) → 3 CH4(g) + 4 Al(OH)3(s)
If aluminum carbide is the limiting reactant, how many moles of the excess reactant are left over
a
37.3 mol
b
4.68 mol
c
7.33 mol
d
131.94 mol
Answer: 4.999 moles of excess reactant will be left over.
Explanation:
Limiting reagent is defined as the reagent which is completely consumed in the reaction and limits the formation of the product.
Excess reagent is defined as the reagent which is left behind after the completion of the reaction.
The number of moles is defined as the ratio of the mass of a substance to its molar mass.
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] .....(1)
Given mass of aluminium carbide = 112 g
Molar mass of aluminium carbide = 143.96 g/mol
Putting values in equation 1:
[tex]\text{Moles of aluminium carbide}=\frac{112g}{143.96g/mol}=0.778mol[/tex]
For the given chemical reaction:
[tex]2Al_4C_3(s)+12H_2O(l)\rightarrow 3CH_4(g)+4Al(OH)_3(s)[/tex]
By the stoichiometry of the reaction:
2 moles of aluminium carbide reacts with 12 moles of water
So, 0.778 moles of aluminium carbide will react with = [tex]\frac{12}{2}\times 0.778=4.668 mol[/tex] of water
Given mass of water = 174 g
Molar mass of water = 18 g/mol
Putting values in equation 1:
[tex]\text{Moles of water}=\frac{174g}{18g/mol}=9.667mol[/tex]
Moles of excess reactant (water) left = 9.667 - 4.668 = 4.999 moles
Hence, 4.999 moles of excess reactant will be left over.
Water can keep engines operating at low temperatures. Which property of water most likely gives it this ability?
A. it boils at around 100°C
B. it has a high heat capacity
C. it is a good lubricant
D. it can change from water to ice
Answer:
B: it has a high heat capacity
Explanation:
When any material has a high specific heat capacity/ heat capacity, it doesn't heat or cool very fast. So water can absorb more heat from the engine and can keep the engine cool or at low temperature for a longer period of time.
The concentration of carbon-14 in a piece of wood from an ancient burial mound indicates that two half-lives of this radioisotope have passed. If the half-life (t 1/2) for carbon-14 is 5730 years, approximately how many years ago did this sample of wood die?
If the half-life for carbon-14 is 5730 years, then it will take 11,460 years to complete die of this sample.
What is half life period?Half life period is a time of decay in which concentration of reactant is left half of its initial concentration, means half of the reactant will convert into product.
Total time of decay will be calculated as:
T = (t)ⁿ, where
t = half life time = 5730 years
n = number of half lives = 2 (given)
On putting values, we get
T = (5730)² = 11,460 years
Hence required time for decay is 11,460 years.
To know more about half life time, visit the below link:
https://brainly.com/question/2320811
Answer:
The first part is 5 and the second part is 28,650
Which of the following are acid formulas? (Choose 2)
NH3
CH3OH
NaOH
HNO3
H2SO4
CH4
Answer:
HNO3 & H2SO4
Explanation:
HNO3 is Nitric acid and H2SO4 is Sulphuric acid
Which of the following must be
TRUE if a solution is to be
considered acidic?
A. [H^+] < [OH)
B. [H^+] > [OH ]
C. KW= [H^+] /[OH]
D. [H^+] =[OH)
Answer:
c
Explanation:
kw=h+bls
El petróleo crudo, es decir, en estado natural,
se encuentra embebido en las rocas porosas de
la corteza terrestre, semejante al agua en una
esponja, y no a manera de lagos subterráneos,
como se cree. Por lo general, el pozo petrolero
contiene en su parte superior una gran masa de
gas. Responde:
a) ¿Qué precauciones se deben tener en la explo-
tación del petróleo?
b) ¿Cuál es el impacto ambiental de la explotación
del petróleo?
c) ¿Qué compromisos debe cumplir una em-
presa que explota el petróleo en relación con el
medio ambiente?
Teresa has taken three tests worth 100 points each. Her scores are 85, 93, and 88. She has one test left to take.
To get an average score of 90, what must the sum of all her test scores be?
a.
400
c.
600
b.
360
d.
300
Answer:
SOrry it makes me writer sotufjksankdn
Explanation:
When temperature drops, (for example from 20 degrees celsius to 10 degrees celsius)
a.) energy increases
b.) particles move slower
c.) particles collide more often
d.) pressure increases
Answer:
In the Celsius scale each degree is one part of 100 degrees. This is because in this scale the difference between boiling and freezing temperatures of water is 100 ° - 0 ° = 100 °, so one degree Celsius is one part of 100.
In the Farhenheit scale, each degree is one part of 180 degrees. This is because in this scale the difference between the boiling and freezing temperatures are 212 ° - 32 ° = 180°, so one degree Fahrenheti is one part of 180.
That means that 1 °C is a larger amount than 1 °C, so 20°C is a larger amount than 20°F.
Conclusion: 20 degree change represents a larger change in Celsius scale.
Explanation:
In the Celsius scale each degree is one part of 100 degrees. This is because in this scale the difference between boiling and freezing temperatures of water is 100 ° - 0 ° = 100 °, so one degree Celsius is one part of 100.
In the Farhenheit scale, each degree is one part of 180 degrees. This is because in this scale the difference between the boiling and freezing temperatures are 212 ° - 32 ° = 180°, so one degree Fahrenheti is one part of 180.
That means that 1 °C is a larger amount than 1 °C, so 20°C is a larger amount than 20°F.
Conclusion: 20 degree change represents a larger change in Celsius scale.
how many moles are in 0.14g of Nitrogen, N2?
Answer:
0.01 moles
Explanation:
14 g contains 1 mole
0.14g contains> (0.14*1)/14
= 0.01 moles
Balance the following equation:
Cr + __02 +_Cr203
Answer:
4Cr + __302 -->_2Cr203.....
Any change in average weather conditions on Earth that lasts for at least several decades is called
Answer:climate change
Explanation:
Someone please help me
Answer:reflection
Explanation:
If 250. ML of water are poured into the measuring cup, the volume reading is 8.45 oz . This indicates that 250. ML and 8.45 oz are equivalent. How many milliliters are in a fluid ounce based on this data?
Answer:
[tex]1oz=29.589ml[/tex]
Explanation:
From the question we are told that:
Initial Volume [tex]v_1=250ml[/tex]
Final Volume [tex]v_2=8.45oz[/tex]
Generally the equation for one ounce is mathematically given by
[tex]1oz=\frac{v_1}{v_2}[/tex]
Therefore
[tex]1oz=\frac{250}{8.45}[/tex]
[tex]1oz=29.589ml[/tex]
Gas particles that are at low temperature and high pressure and are close to changing phases are considered:
a)Real Gases
b)Ideal Gases
c)Both Ideal and Real Gases
How many formula units are there in 14.50 moles of any compound?
___X 10^___formula units
Answer:
8.73 × 10²⁴ formula units
Explanation:
To calculate the number of formula units a substance contain, we multiply the number of moles by Avagadro number (6.02 × 10²³)
number of formula units = 14.50 moles × 6.02 × 10²³
= 87.29 × 10²³
= 8.73 × 10²⁴ formula units.
Can someone please help, 20 points
Draw 3-ethyl-2,4-dimethyl octanoic acid
3-ethyl-2.4-dimethyl-octanoic acid
High levels and long periods of stress can increase a person’s risk for many diseases.
True
False
Answer:
true
Explanation:
The chemical equation for zinc in hydrochloric acid is: Zn + HCI = ZnCl2 + H2
Does the above equation demonstrate the law of conservation of mass as it is currently written? Explain why or why not.
Answer: No it does not
Explanation:
The law of conservation of mass states that mass is neither created nor destroyed and in this equation you start with 1 molecule of Cl and 1 of H, but on the reactants side you end up with 2 of each. To make it follow the law of conservation of mass you would have to balance the equation