Answer:
melting and solidification
Answer: MELTING
Explanation:
Hydrofluoric acid (HF) can be prepared according to the following equation:
CaF2 + H2SO4 2 HF + CaSO4.
How many grams of HF can be prepared from 75.0 g of H2SO4 and 63.0 g of CaF2?
In the above problem, which reactant is limiting and which is in excess?
Given the balanced equation:
( Reaction type : double replacement)
CaF2 + H2SO4 → CaSO4 + 2HFI
We can determine the number of grams prepared from the quantity of 75.0 H2SO4, and 63.0g of CaF2 by converting these grams to moles per substance.
This can be done by evaluating the atomic mass of each element of the substance, and totaling it to find the molecular mass.
For H2SO4 or hydrogen sulfate it's molecular mass is the sum of the quantity of atomic mass per element. H×2 + S×1 + O×4 = ≈1.01×2 + ≈32.06×1 + ≈16×4 = 2.02 + 32.06 + 64 = 98.08 u (Dalton's or Da) or g / mol.
For CaF2 or calcium fluoride, it's molecular mass adds 1 atomic mass of calcium and 2 atomic masses of fluoride due to the number of atoms.
Ca×1 + F×2 = ≈40.07×1 + ≈19×2 = 40.08 + 38 = 78.07 u (Da or Dalton's) or g / mol.
The limiting reactant in the given balanced reaction is sulphuric acid. The mass of HF produced from 75 g of H₂SO₄ is 30 g.
What is limiting reactant?The limiting reactant in a species is the reactant which is fewer in amount and thus determine the yield of the product.
In the given reaction, one mole of calcium fluoride reacts with one mole of sulphuric acid to give two moles of HF. The molar mass of calcium fluoride CaF₂ is 78 g/mol the weight taken here is 63 g. Thus number of moles is 63/78 = 0.87 moles.
The molar mass of sulphuric acid H₂SO₄ is 100g/mol. The weight taken here is 75 g and thus, number of moles is 75/100 = 0.75 moles. One mole of calcium fluoride need one mole of H₂SO₄ . Thus 0.87 neede 0.87 moles of H₂SO₄ . But here we have only 0.75. Thus it is the limiting reactant.
As per the reaction, one mole or 100 g of H₂SO₄ produce 2 moles or 40 g of HF (molar mass = 20 g/mol). Thus mass of HF produced from 75 g is calculated as follows:
mass of HF = (75 × 40)/100
= 30 g.
Hence, mass of HF produced in this reaction is 30 g.
To find more about limiting reactant, refer the link below:
https://brainly.com/question/2948214
#SPJ2
When a liquid freezes into a solid, the particles of the substances *
lose energy
gain energy
move faster
disappear
Answer:
Lose energy
Explanation:
The molecules are moving from a liquid (molecules slide past one another) to a solid (molecules barely move) so are losing energy
What type of reaction is illustrated?
The ionization energies for removing successive electrons from sodium are 496 kJ/mol, 4562 kJ/mol,
6912 kJ/mol, and 9544 kJ/mol. The great jump in ionization energy after the first electron is removed
indicates that
Select one:
O a. sodium has four or five electrons.
O b. the atomic radius has increased.
c. a d-electron has been removed.
d. the noble gas configuration has been reached.
Answer:
D
Explanation:
The high jump of ionization energy indicates that we are trying to remove electron from noble gas configuration state.
The ionization energy data specifies that the Elements are from group 1 at period 3 or greater.
Removing the first electron require 496 kJ and the second ionization energy jump significantly due to the removal of electron from the noble gas configuration which is logical because electron try to maintain the especially stable state.
An element found in groups 3-12 of the periodic table is classified as a[n]
Answer:
Transition Metals
Explanation:
Hope this helped :)
GUYS I NEED THIS ASAP
Hurry please quick summary
give 7 and example of how each wave in the EM spectrum in used in our daily lives
The box in the above picture is falling from the top of a building to the ground. Two major forces are acting on the box as it falls. Which force is represented by the arrow labeled Q?
A.
the force of magnetism
B.
the force of gravity
C.
the net force of the object
D.
the force of air resistance
Answer:
I think it's B
Explanation:
apologies if I get this wrong
Answer:
The correct answer is B. The force of gravity.
Explanation:
Gravity affects all objects falling through the Earth's atmosphere. Gravity pulls down on a falling object.
( I got it on study Island as well )
Liquid Nitrogen’s temperature is minus what degress
Answer:
-320f
Explanation:
if a baloon filled with dry hydrogen weighs 35 gram,but weighs 440 grams when filled with the vapour of an organic compound. calculate the vapour density and RMM of the organic compound.
Answer:
1) The vapor density of the organic compound is approximately 12.57
2) The relative molar mass (RMM) of the organic compound is approximately 25.14 grams
Explanation:
1) The mass of the balloon filled with dry hydrogen = 35 grams
The mass of the balloon filled with vapor of an organic compound = 440 grams
The vapor density = (Weight of a given volume of gas)/(Weight of equal volume of hydrogen)
The vapor density of the organic compound = (440)/(35) ≈ 12.57
The vapor density of the organic compound ≈ 12.57
2) The relative molar mass (RMM) = 2 × vapor density
The relative molar mass (RMM) of the organic compound = 2 × vapor density of the organic compound
The relative molar mass (RMM) of the organic compound ≈ 2 × 12.57 ≈ 25.14 grams
The relative molar mass (RMM) of the organic compound ≈ 25.14 grams
What is the difference between the substances represented by the symbols Co and CO
Answer:
Be careful about when to use capital letters. For example, CO means a molecule of carbon monoxide but Co is the symbol for cobalt
Explanation:
Which statement best describes scientific laws? A) Scientific laws are scientists' opinions of why events occur. B) Scientific laws are facts that describe observed reoccurring natural events. C)Scientific laws explain why natural events occur. D) Scientific laws were theories that have been proven to be true.
Answer:
Option B and D seem to be correct
Explanation:
As a scientific law is a statement which is bases on repeated experimental observations that describes some aspects of nature and also they are were theories that have been proven to be true as a theory become a law when the experiment agree with the theory and no contrary opinions so according to my studies , B and D options are seems to be correct.
What is the electron configuration for boron (B)?
Answer:
[He]2s2 2p1.
that is the answer have an amazing day. Remember your an amazing person for who you are.
A bulldozer does 15,000 J of work lifting dirt 15 m up to get it out of a hole. How much force did the bulldozer use to accomplish this task?
Answer:
The answer is 3000 NExplanation:
The amount of force can be found by using the formula
[tex]f = \frac{w}{d} \\ [/tex]
w is the workdone
d is the distance
From the question we have
[tex]f = \frac{15000}{5} \\ [/tex]
We have the final answer as
3000 NHope this helps you
If 8.2 g of sodium ethanoate produced 560 cm3 of methane (at s.t.p.). which one of the following is the percentage yield of the reaction;
A 2.5
B 4.0
C 12.0
D 25.0
The percentage yield of the reaction : 25%
Further explanationC₂H₃NaO₂(CH₃COONa)- Sodium ethanoate(MW=82,0343 g/mol)
Reaction
CH₃COONa + NaOH⇒CH₄+Na₂CO₃
mol CH₃COONa :
[tex]\tt \dfrac{8.2}{82.0343}=0.1[/tex]
mol CH₄=mol CH₃COONa = 0.1
mass CH₄ (MW=16.04 g/mol) :
[tex]\tt 0.1\times 16.04=1.604~g[/tex]⇒ theoretical
mol of 560 cm³(0.56 L) of methane (⇒1 mol = 22.4 L at STP) :
[tex]\tt \dfrac{0.56}{22.4}=0.025~mol[/tex]
mass CH₄ :
[tex]\tt 0.025\times 16.04=0.401~g[/tex]
[tex]\tt \%yield=\dfrac{0.401}{1.604}\times 100\%=25\%[/tex]
describe how electricity moves through wires
Four students are carrying out different laboratory procedures. Piroja is mixing baking soda and vinegar to see if it reacts. Jason is heating salt water over a burner until the water evaporates. Kali is putting crushed ice and ice cubes on a table to see which melts first. Francisco is separating iron filings from sand using a magnet. Which experiment relies on convection? Piroja’s experiment Jason’s experiment Kali’s experiment Francisco’s experiment
Answer: Jason experiment
Explanation:
I just took the test
Answer: Jason's Experiment
Why do clothes stick together when coming out of a dryer? And do the clothes start off as neutral?
here is what came up when i searched it up:
"The attraction between protons and electrons can also make clothes stick together in the dryer. When you dry clothes in the dryer, different fabrics rub together, and electrons from a cotton sock (for instance) may rub off onto a polyester shirt."
Sometimes, clothes can get stuck together after they come out of a dryer because of static electricity.
No, clothes may not start off as neutral. Whether clothes have static charges before going into the dryer depends on different things.
Why do clothes stick together when coming out of a dryer?Static electricity happens when certain things touch and create an uneven amount of electrons. This can cause one material to have a positive charge and the other to have a negative charge. When clothes move and touch each other in a dryer, this rubbing can cause static electricity.
If the clothes are cleaned and dried correctly, they should have no charge or be evenly charged.
Read more about clothes here:
https://brainly.com/question/18269825
#SPJ6
What two uses are used for oxygen?
Answer:
I think your lumgs and your heart but I could be tottaly wrong
5) If an atom has a positive charge what is it called?
Answer:
An atom that has a negative or positive charge it is called an ion.
Answer:
It''s called a Cation
Explanation:
How do the alveoli in the lungs move oxygen and nutrients into the bloodstream? 1.Gravity 4.Time 2.Diffusion 5.Pressure 3.Magnetic force
Answer:
2.Diffusion
Explanation:
As we metabolize certain nutrients for the correct functioning of our cells, carbon dioxide is produced as a result. We need oxygen in order to metabolize them, so we need to have a system to incorporate it, and to eliminate the carbon dioxide produced.
This system is provided by the interaction between the respiratory system, which allows the enter of oxygen into the body and gets rid of the carbon dioxide, and the circulatory system, which acts transporting carbon dioxide and oxygen to and from the lungs, respectively.
The surface available for the gaseous exchange is enlarged by the pulmonary alveoli. The alveoli are the terminal aerial spaces of the respiratory system and the structures where the exchange between the air and blood is produced. Each alveolus is surrounded by a net of capillaries, where oxygen is freed from the hemoglobin and moves into the cells by diffusion. Carbon dioxide, diffuses out of the cells into the capillaries, where most of it dissolves in the plasma of the blood.
calculate the number of neutrons in potassium-40.
Considering the definiton of atomic number and atomic mass, the number of neutrons of the potassium is 21.
All atoms are composed of a central nucleus in which there are particles with a positive electric charge, the protons, and a neutral charge, the neutrons, around which other particles with a negative electric charge, which are electrons, move.
Atoms of different elements have different amounts of protons. The atomic number (which is identified by the letter Z) indicates the amount of protons that is present in the nucleus of an atom. This number is then responsible for defining the electronic configuration of the atom and the chemical properties of the element.
On the other side, the atomic mass (A) is defined as the sum of number of protons and number of neutrons:
Atomic mass = Number of protons + Number of neutrons
In this case, the potassium (K) elements has atomic number 19. That means, the number of of protons is equal to 19. And the atomic mass is 40. So, the number of neutrons is calculated as:
40= 19 + Number of neutrons
Solving:
Number of neutrons= 40 - 19
Number of neutrons= 21
Hence, the number of neutrons of the potassium is 21.
Learn more:
https://brainly.com/question/5527493?referrer=searchResultsbrainly.com/question/11837355?referrer=searchResults brainly.com/question/1758023balance this chemical equation pleaseee
For every action, there is an equal and opposite reaction.
Does the statement describe a scientific law?
Answer:
yeah its newton's third law
Explanation:
Name two or more body systems that work together.
Describe how they work together.
Answer:
All of your body systems have to work together to keep you healthy. Your bones and muscles work together to support and move your body. Your respiratory system takes in oxygen from the air
Explanation:
why is the moisture of cirrus clouds mostly in the solid state
Answer:
Wind is the horizontal movement of air, transporting energy transferred from the earth's surface as sensible and latent heat. Sensible heat is transferred by the processes of conduction and convection. Conduction transfers energy within a substance, and convection transfers energy through the vertical movement of the heated substance. Latent heat is the transfer of energy by transforming the substance itself. As you recall, water has the ability to exist as liquid, gas or solid. The transformation from liquid to gas is called evaporation; the reverse process, from gas to liquid, is called condensation; from liquid to solid is known as solidification (freezing); and from solid to liquid, fusion (melting). Water can also be transformed directly from solid to gas (sublimation), or the reverse, through a process called deposition. We will see these various processes in the formation of clouds.
Explanation:
if I did not give answer then i hope i at least helped!
which element in the alkali group will have the lowest first ionization energy?
Fluorine
Explanation:
F- has the lowest ionisation energy
Which of the following characteristics indicates that an atom is unstable?
Answer:
I think is d.
Explanation:
particles that make up the nucleus are balanced. An atom is unstable (radioactive) if these forces are unbalanced; if the nucleus has an excess of internal energy. the Instability of an atom's nucleus may result from an excess of either neutrons or protons.
I'm not sure, but hope it helps.
Forming very strong bond characteristics indicates that an atom is unstable. Hence, option D is correct.
What is an atom?An atom is any particle of matter which contains at least one proton.
An atom is unstable if the nucleus has an excess of internal energy.
The Instability of an atom's nucleus may be due to an excess of either neutrons or protons.
Hence, forming very strong bond characteristics indicates that an atom is unstable.
Learn more about atom here:
brainly.com/question/1566330
#SPJ5
Which best describes what is occurring when a door is almost closed and rays of light fan out from the small opening? absorption interference refraction diffraction
Answer:
The correct answer is Option D (diffraction).
Explanation:
Diffraction has been known as a mechanism through which light rays divide across clusters of darkness and light rather than into the colors of the rainbow. That is the twisting of such an obstacle across the sun. In this case, the challenge has been the door from which the illumination moves and bends.Other alternatives are not relevant to the specified case. So, the alternative above would be appropriate.
Answer: D
Diffraction
Explanation:
E D G E 2 0 2 0