Answer:
A = 1.627 ×10²³ molecules of CF₂Cl₂.
B = 809.4 ×10²³ molecules of Fe(NO₃)₂.
C = 0.03117 ×10²³ molecules of C₈H₁₈.
D= 1116 ×10²³ molecules of CaO.
Explanation:
A)
Given data:
Mass of CF₂Cl₂ = 32.66 g
Number of moles = ?
Number of molecules = ?
Solution:
Number of moles = mass/ molar mass
Number of moles = 32.66 g/ 120.9 g/mol
Number of moles = 0.2701 mol
Number of molecules:
1 mole = 6.022×10²³ molecules
0.2701 mol×6.022×10²³ molecules / 1mol = 1.627 ×10²³ molecules of CF₂Cl₂.
B) Given data:
Mass of Fe(NO₃)₂ = 24.2 Kg (24.2×1000 = 24200 g)
Number of moles = ?
Number of molecules = ?
Solution:
Number of moles = mass/ molar mass
Number of moles = 24200 g/ 180 g/mol
Number of moles = 134.4 mol
Number of molecules:
1 mole = 6.022×10²³ molecules
134.4 mol×6.022×10²³ molecules / 1mol =809.4 ×10²³ molecules of Fe(NO₃)₂.
C) Given data:
Mass of C₈H₁₈= 0.5912 g
Number of moles = ?
Number of molecules = ?
Solution:
Number of moles = mass/ molar mass
Number of moles = 0.5912 g/ 114.22 g/mol
Number of moles = 0.005176 mol
Number of molecules:
1 mole = 6.022×10²³ molecules
0.005176 mol×6.022×10²³ molecules / 1mol =0.03117 ×10²³ molecules of C₈H₁₈.
D) Given data:
Mass of CaO = 104 Kg (104×1000 = 104,000 g)
Number of moles = ?
Number of molecules = ?
Solution:
Number of moles = mass/ molar mass
Number of moles = 104,000 g/ 56.1 g/mol
Number of moles = 1854 mol
Number of molecules:
1 mole = 6.022×10²³ molecules
1854 mol×6.022×10²³ molecules / 1mol = 1116 ×10²³ molecules of CaO.
An ice cube is placed in a glass of water. Which of the following best explains the
heat transfer?
A: The thermal
is moving
from the water to from the ice cube into the water into the water
causing the
temperature of
the water to
increase.
B: the thermal energy is moving from the water to the ice cube causing the temperature of the water to decrease
C: the thermal energy is moving from the ice cube into the water causing the temperature of the water to increase
D: the thermal energy is moving from the ice cube into the water causing the temperature of the water to decrease.
D: the thermal energy is moving from the ice cube into the water causing the temperature of the water to decrease.
Calculate the average atomic mass of silver if 13 out of 25 atoms are silver -107 and 12 out of 25 atoms are silver -109
Answer: 107.96amu
Explanation:
(107x.52)+(109x.48)
55.64+52.32=107.96
In a science demonstration, a teacher mixed zinc (Zn) with hydrogen chloride (HCl) in a flask and quickly attached a balloon over the mouth of the flask. Bubbles formed in the solution and the balloon inflated.
What most likely occurred during this demonstration?
The Zn and HCl both retained their identity.
Either Zn or HCl, but not both, retained its identity.
Evaporation of one of the substances occurred.
One or more new substances formed.
One or more new substances formed.
Answer:
d
Explanation:
100 quiz
What would pressure be if volume was 0
Answer:
The lower the temperature, the lower the pressure inside of the sphere. If the exact values were plotted out, a linear relationship would be apparent. Extrapolating this line to the point where there would be no pressure yields absolute zero, which is about -273.15 degrees Celsius.
Explanation:
Find the area of a rectangle with a length of 10cm and a width of 7cm.
A.70cm
B.17 cm
C.17cm2
D.70cm2
Answer:
D
Explanation:
You would do 10*7 witch would be 70 then cm2 so the answer is 70cm2
What are alternative periodic tables
Reducing child __________, or rate of death, is one of the primary goals of the UN’s Millennium Development Goals.
A.
mortality
B.
maternity
C.
infirmity
D.
infection
Answer: A
Explanation: Mortality means death. And it is a primary goal of Development Goals
Reducing child mortality, or rate of death, is one of the primary goals of the UN’s Millennium Development Goals and the correct option is option A.
What is Mortality?Mortality is defined as the state of the individual being dead. The mortality rate is the death rate of a population which is calculated on the basis of the deaths in the particular region.
Mortality as one of the components of demography is measured as mortality rate.
Mortality meaning provides the basis for mortality rate and its estimation. Mortality is the possibility of and susceptibility to death, and hence, the rate of mortality or the death rate is the measurement of the number of deaths that occur in a particular population, scaled to the size of that population per unit of time.
Therefore, Reducing child mortality, or rate of death, is one of the primary goals of the UN’s Millennium Development Goals and the correct option is option A.
Learn more about Mortality, here:
https://brainly.com/question/6344227
#SPJ3
7. Electrons that are free to move in a metal are referred to as ________ electrons.
A.magnetic
B.valence
C.electrostatic
D.cation
Answer:
D; Cation
They are the valence electrons that can move between two metal molecules.
I am a common cation that is found in the alkali group. I am found in salt. I have a +1 charge. What am I?
Answer:sodium
Explanation:
Sodium
HELPS MEEEEEEEEEEEEE!!!!!!!!!!!!!
Conduction is ______________.
A. When particles transfer energy by touching.
B. None of these
C. When the sun warms an object.
D. The flow between warm and cool sections of a fluid.
Answer:
a
Explanation:
Answer:A. When particles transfer energy by touching.
Example: After a car is turned on, the engine becomes hot.
9. First identify the following as either homogeneous substances or
heterogeneous mixtures. Then further classify as either elements,
compounds or mixtures:
a. Earth
i. Air
b. H(9) I
j. CuSO4(s)
C. Cuso, (aq)
k. NaCl (1)
d. Magnesium solid
1. Methane gas
e. Na (s)
m. Antimony (1)
f. Sugar (1)
n. H20 (1)
g. C.H2O. (aq)
o. 02 (9)
h. NaCl (aq)
p. CO (9)
Answer:
a few days ago of course I was a in the my life pro chef chef cooking channels and then the first first place to for the you know what do not you can be you know how much
does anyone know how to do this??????
Answer:
you have to answer about what Emmy Noether was known for and how she accomplished her goal! For example Dr. Martin Luther King was known for his peaceful protests and his famous "I Have a Dream". He accomplished this goal by never giving up and sticking to his morals! I hope this helped!! ♡♡ (BTW love your profile picture)
Calculate the mass percent of sulfuric acid in a solid sample given a 0.8390g sample of that solid required 32.22 mL of 0.2012 M NaOH for neutralization.
A) 62.11
B) 2.64
C) 37.89
D) 75.78
E) 1.27
Please give an answer and an explanation, thanks!
Answer
C
Explanation:
i remember learning this
Mass percentage does not have any unit as numerator and denominator contains the same unit. The percentage of sulfuric acid in solid sample is 38.07%.
What is percentage by mass?Mass percentage represents the the percentage of each element that is making a particular compound.
Mathematically,
Percentage of mass = (component’s mass ÷ total mass) x 100%
[tex]\rm 2 NaOH aq + H _{2} SO _{4} aq → Na _{2}SO _{4}aq + 2 H _{2} O[/tex]
Volume of NaOH solution = 32.22 mL = 0.03222 L
Concentration or molarity of the NaOH solution = 0.2012 M
Moles of NaOH : 0.03222×0.2012=0.006444mol
2 moles of sodium hydroxide reacts with 1 mole of sulfuric acid.
0.006444mol of sodium hydroxide reacts with =0.006444÷2=0.003222mol of sulfuric acid.
Mass of sulfuric acid neutralized = 0.003222 moles × 98.08 g/mol =0.31601376g
Percentage of sulfuric acid in solid sample= (0.31601376g÷0.8390g)×100=38.07%
Thus the percentage of sulfuric acid in solid sample is 38.07%.
To learn more about mass percentage, here:
https://brainly.com/question/27429978
#SPJ2
SCIENCE A meteorologist uses a weather map to explain an upcoming change in weather. The map shows a blue line with triangles approaching a red line with semicircles. Based on the map, which weather prediction is most valid? (1 point) A a significant drop in temperature will occur across the area. B There is no chance of precipitation in the forecast. C Warm temperatures will replace cold temperatures. D Humidity levels will rise.
Answer:
The correct option is D) Humidity levels will rise
Explanation:
A rise in humidity means that it is most likely there is going to be a rain.
When blue semi-circle lines with triangles approach red semi-circle lines it is a situation where cold front is approaching a warm front.
The resultant effect is that the warm and cold air both come to a standstill. This will most likely trigger cloud and fog and may even lead to rain.
Cheers
Which model represents an element?
Answer: Water. Earth. Fire. Air.
Explanation: the four nations lived together in harmony. Then, everything changed when the Fire Nation attacked. Only the Avatar, master of all four elements, could stop them, but when the world needed him most, he vanished. A hundred years passed and my brother and I discovered the new Avatar, an airbender named Aang. And although his airbending skills are great, he has a lot to learn before he's ready to save anyone. But I believe Aang can save the world."
Which roller coaster
car has the least potential energy due to gravity
Answer:
the roller coaster car with the least potential energy would be the one at the bottom of the roller coaster
Explanation:
Hope this helped
Which of these would have particles with the highest kinetic energy?
ice
water
water vapor
Answer:
water vapor
Explanation:
because gas molecules moves the fastest
Answer:
water vapor
Explanation:
Liquid water molecules have less freedom to move around. While molecules of water vapour have more freedom to move around as there is larger space between the molecules. Hence, the kinetic energy of water molecules is more as compared to the kinetic energy of liquid water
Which is a change or signal in the environment that can make an organism
react? *
stimulus
O reaction
impulse
O
response
Answer:
I'm pretty sure its stimulus
Is fire considered matter
Answer:
Fire is a state of matter
Explanation:
Fire is the fourth state if matter called plasma fire is one of thr naturally occuring plasmas we have in existance on earth!
An object has a mass of 20 g and volume of 10 cm. Enter the numerical value for the density of the object in units of g/cmº
Answer:
density = 2g/cm³
Explanation:
density = mass/volume
mass = 20g
volume = 10cm³
density = 20g/10cm³
density = 2g/cm³
Pieces of inorganic or organic materials that come from rock and are
deposited by wind, water, or ice are called...
1.weathering
2. sediment
3.erosion
4.drought
Answer:
Sediment
Explanation:
Example of Anchoring Bias
Answer:
Here is an example of anchoring Bias
If I were to ask you where you think Apple’s stock will be in three months, how would you approach it? Many people would first say, “Okay, where’s the stock today?” Then, based on where the stock is today, they will make an assumption about where it’s going to be in three months. That’s a form of anchoring bias. We’re starting with a price today, and we’re building our sense of value based on that anchor.
Anchoring bias occurs when people rely too much on pre-existing information or the first information they find when making decisions. For example, if you first see a T-shirt that costs $1,200 – then see a second one that costs $100 – you're prone to see the second shirt as cheap.
Anchoring or focalism is a term used in psychology to describe the common human tendency to rely too heavily, or "anchor," on one trait or piece of information when making decisions.
Hope that helped if it did please give me brainiest Thanks <333 :3
You can separate air into two different substances by density. What is air?
O A. A mixture
OB. A compound
C. An atom
D. An element
SUB
Please help will give brownies
Answer:
1.A 2.B
Explanation:
your welcomme glade to help
Na + HCI → H2 + NaCl
Based on your data, how are elements arranged into chemical families?
Answer:
Based on their groups
Explanation:
Answer:
They are arranged vertically depending on how many valence electrons they have, if they have the same amount, they will have the same chemical family in each column.
What is the charge of an Pb atom with 81 electrons?
Answer:
+1 Because there are 82 protons.
Explanation:
A brick delivery truck parks on a roadside scale that measures 4 m by 6 m. If the brick truck weighs 60 000 N, what pressure does the scale put on the spring below?
Explanation:
Area = Length × Breadth
A = 4 × 6
A = 24m square/ 24m sq.
Force = Pressure × Area
Force = 60,000 N/ 60,000 Newton
Pressure = Force/ Area
P = 60,000/24
P = 2500 Pa
Which of the following conclusions can be made about the sedimentary layers?
bed 2 was deposited after bed 3
bed 2 was deposited before bed 3
bed 3 was deposited before bed 1
bed 1 is the youngest
Answer:
I think it's the second one im not sure tho
Hope this helps :)
Use the information given to calculate the average atomic mass of element Z. Z- 56 is 70% abundant and Z-59 is 30% abundant.
Answer:
56.9 amu
Explanation:
Depending on the number of isotopes an element has, the Average atomic mass of isotopes of an element can be calculated using:
(atomic mass of isotope1 × decimal abundance of isotope1) + (atomic mass of isotope2 × decimal abundance of isotope2)
According to this question, two isotopes of element Z were given
- Isotope Z- 56 with atomic mass 56 is 70% abundance. This means that its decimal abundance is 0.70
- Isotope Z- 59 with atomic mass 59 is 30% abundance. This means that its decimal abundance is 0.30
Therefore, average atomic mass of element Z is:
= (56 × 0.70) + (59 × 0.30)
= (39.2) + (17.7)
= 56.9