If you have 7.3g of solid calcium and it takes 62.3J of heat to melt it at 842°C. what would the heat of fusion for calcium?
Answer:
fttttggttfvvgfrr ccsfgt chg chu rdh fig ffhfr
Answer:
To solve this problem, you'll need the formula that relates heat energy to mass and heat of fusion:
q = m·ΔHf
where
q = heat energy
m = mass
ΔHf = heat of fusion
Explanation:
62.3J ÷ 7.3g = ΔHf
8.53 J/g = ΔHf
4.18 cal/g = ΔHf
An atom contains 22 protons and 26 neutrons. What is its mass number?
Answer:
47.867
Explanation: It's Titanium because the atomic number is the number of protons.
A nucleus emits an alpha particle. What happens to the mass
number and the atomic number of that nucleus?
Answer:
the mass number decreases by 4 and the atomic number decreases by 2
Which structure is responsible for producing pollen in flowering plants?
Answer:
The stamen!
The stamen is often made up of anthers and filaments
Rain that containing excess of acid is called
Answer:
The rain containing excess of acid I called acid rain
Answer:
acid rain
Explanation:
Thats literally what its called
need points & are good at science?
Answer:
A region 2
Explanation:
Explain (not just list) where you observe reflection, refraction, and absorption of light in your everyday activities
Answer:
Reflection: you look in the mirror. Refraction: You put a straw in a glass of water, and it looks like it broke. Absorption: If you have a black sweater and you wear it out in the cold, the black sweater is going to hold in heat better than a lighter sweater because the black sweater absorbs light .
Why do molecular compounds have low melting points and low boiling points relative to ionic substances?
Answer:
The melting and boiling points of molecular compounds are generally quite low compared to those of ionic compounds. This is because the energy required to disrupt the intermolecular forces between molecules is far less than the energy required to break the ionic bonds in a crystalline ionic compound
What did Albert Einstein say was the nature of electromagnetic radiation?
Answer:
Albert Einstein proposed the wave-particle theory of electromagnetic radiation. This theory states that electromagnetic energy is released in discrete packets of energy—now called photons—that act like waves.
Temperatures in the upper atmosphere (thermosphere) reach 1500°C (2700°F), yet it does not produce
enough heat to burn you. Why?
if im not mistaken its because the ozone layer
Who arranged the elements according to atomic mass, and used the arrangement to predict the properties of missing elements.
a john dalton
b henry mosely
c dmitri mendeleev
d antoine lavoisier
Answer:
i think it's C
Explanation:
But if it's wrong,im so sorry
Answer:
C.
Explanation:
the answer is C dmitri mendeleev
What is heat energy
Answer:
Explanation:
ok, so heat energy is a result to moving particles which are atoms molecules or ions in solids,liquids and gasses. And heat energy can be moved from an object to a other object. The transfer or the flow is different in temperature between the two different of objects which is called heat.
Hope this is useful!
Calculate the number of moles in 19.3g of NaCl
Answer: 0.33 mole
Explanation:
Let the number of moles be represented by x.
We should note that 1 mole of NaCl = 58.44g
Therefore, the number of moles in 19.3g of NaCl will be :
= 19.3/58.44
= 0.33 mole
Therefore, the number of moles in 19.3g of NaCl is 0.33 mole
Which factor affects the amount of gravitational potential orgy at object but
and the amount of kinetic energy an object has?
A mass
B. speed
C. height
D. particles
I need help
Answer:
Speed
Explanation:
Answer:
mass
Explanation:
your welcome
How many layers of paint are there on the typical manufactured vehicle?
Answer:
3 sometimes 4
Explanation: there are usualy
3 layers of paint but sometime manufacterers add paint protection film to bring the total up to 4
In the molar volume of a gas lab, a student
failed to determine the actual volume of
the flask used to collect the gas and
instead used the marking on the flask,
125 ml, as the volume. How will this affect
the student's results?
Answer:
A
Explanation:
Which path shows how gravity causes water to move?
Answer:
run off
Explanation:
Answer: The answer is stream --> Tributary --> River --> Lake
HELP PLEASE!!!!! true or false science questions and normal questions
1. true or false: A compound is a substance made of entirely of a single type of atom
2. true or false: fig is a mixture ogpf water droplets in air
3. draining the liquid from a mixture of a liquid and a solid after the particles of the solid substance have settled
^ ^
sifting
decanting
filtration
please write if its true or false and which of the words apply to qs 3 TvT
Answer
What website is this question on?
Explanation:
Answer:
1. true or false: A compound is a substance made of entirely of a single type of atom. answer: true
2. true or false: fig is a mixture of water droplets in air. imma just say its false
Explanation:
3. draining the liquid from a mixture of a liquid and a solid after the particles of the solid substance have settled
^ ^
answer : filtration
sifting
decanting
filtration
by the way ur teacher is a FiretrUCKING geek he/she looked this up on a quiz
What are the 2 basic parts of an atom?
Answer:
nucleus and electrons
Explanation:
nucleus contains protons and neutrons
What is the difference between enzyme and any other chemical catalyst?
Answer:
Enzymes and catalysts both affect the rate of a reaction. The difference between catalysts and enzymes is that enzymes are largely organic in nature and are bio-catalysts, while non-enzymatic catalysts can be inorganic compounds. ... Neither catalysts nor enzymes are consumed in the reactions they catalyze.
Explanation:
MARK ME
You have a 5-liter container with 1.30 x 1024 molecules of ammonia gas (NH3) at STP.
How many molecules of argon gas (Ar) are in an identical container at the same temperature and pressure?
1). 2.00 x 1023
molecules
2). 6.02 X 1024
molecules
3). 1.30 X 1024
molecules
4). 6.02 x 1023
molecules
Answer:
3). 1.30 × 10^(24) molecules
Explanation:
From avogadro's law which state that equal volume of all gases at the same temperature and pressure contain the same number of molecules.
We can relate it to this question as;
V₁/n₁ = V₂/n₂
Where;
V₁ is initial volume
n₁ is initial number of molecules
V₂ is final volume
n₂ is final number of molecules
Thus at STP, we have V₁ = V₂ and as such Plugging in the relevant values gives;
5/(1.30 x 10^(24)) = 5/n₂
n₂ = 1.30 x 10^(24) molecules
Answer:
1.30 X 1024 molecules
Explanation:
just took the test :D
have a miraculous day!!! <3
4NH3 + 502 -> 4NO + 6H20 How many grams of nitrogen monoxide (NO) will be produced from 2.50 g oxygen (02)?
gram of NO=5
2NO = 2N+O2
2×2.50=x
x=5
The mass of nitrogen monoxide produced from 2.5 grams of oxygen is 1.875 grams
4NH₃ + 50₂ → 4NO + 6H₂0
The limiting reagent is 0₂ because the least moles of this are used in the reaction.
Therefore, it will determine the amount of product formed.
From the chemical reaction above
10(16) g of 0₂ gives (4×14 + 4×16) g of NO
2.50 g of 0₂ will give ? of NO
cross multiply
mass of NO formed = 2.50 × 120 / 160
mass of NO formed = 300 / 160
mass of NO formed = 1.875 grams
learn more on mass here: https://brainly.com/question/14269180
During which eon was the earth made of land masses all clumped together in one supercontinent called Rodinia?
A) Proterozoic
B) Phanerozoic
C) Hadean
D) Archean
(GIVING 20 POINTS)
During the Proterozoic eon was the earth made of land masses all clumped together in one supercontinent called Rodinia. Therefore, option A is correct.
Why is it called the Proterozoic eon?The Archean Eon is followed by the Proterozoic Eon, which spans 2.5 billion years to 541 million years old and is known as the "early life" eon. The majority of the continents' center regions were developed by this time, and the plate tectonic process had begun.
The Proterozoic is currently understood based on geological, geochemical, and fossil evidence. The Cambrian epoch and an explosion of various species at the beginning of the Phanerozoic eon both originated at the conclusion of this eon.
During the Proterozoic Era, Rodinia was a supercontinent that included nearly all of Earth's landmasses for around 450 million years (2.5 billion to 541 million years ago).
Thus, option A is correct.
To learn more about the Proterozoic eon, follow the link:
https://brainly.com/question/20700965
#SPJ3
during a heating or cooling process, how are changes in enthalpy and temperature related?
Answer:
answer this and ill answer that
Explanation:
during a heating or cooling process, how are changes in enthalpy and temperature related?
What is the mass of 8.03 mole of NH3? (NH3 is 17g/mol)
Answer:
the mass of 8.03 mole of NH3 is 136.51 g
Explanation:
The computation of the mass is shown below:
As we know that
Mass = number of moles × molar mass
= 8.03 mol × 17 g/mol
= 136.51 g
Hence, the mass of 8.03 mole of NH3 is 136.51 g
We simply multiplied the number of moles with the molar mass so that the mass could come
1 - 2Na + O2 ➔ Na2O Balanced Not Balanced
2 - 2NaNO3 ➔ 3NaNO2 + O2 Balanced Not Balanced
3 - 2Al + 3Cl2 ➔ AlCl3 Balanced Not Balanced
4- 2P + 3I2 ➔ 2PI3 Balanced Not Balanced
5 - 2Al + 2H3PO4 ➔ 3H2 + 2AlPO4 Balanced Not Balanced
6 - H2O2 ➔ 2H2O + O2 Balanced Not Balanced
7 - 2HCl + CuO → CuCl2 + H2O Balanced Not Balanced
Answer:
1 not
2 not
3 not
4 balanced
5 not
6 not
7 balanced
Explanation:
the amount of elements must be equal in the reactant and products
Which of the following is an example of physical property?
A- corrosion
B-malleability
C-tarnish
D-rust
Answer:
B. Malleability
Explanation:hope it help
What is the molecular formula of a compound that contains 66% Ca and 34% P and
has a molar mass of 182.18 g/mol?
Answer:
Ca3P2
Explanation: find out what 66% of the molar weight of the molecule is and then find out how many moles of Ca that would be by dividing it by the molar weight of Ca
then do the same for P
What is the total amount of heat needed to change 2.25 kg of silver at 0.0°C to 200.0°C? The specific heat of silver is 0.129 J/g·°C (2.25 kg = 2250 g)
Answer:
Q = 5805 Joules.
Explanation:
Given the following data;
Mass = 2250g
Specific heat capacity of silver = 0.129 J/g·°C
Initial temperature, T1 = 0.0°C
Final temperature, T2 = 200.0°C
To find the quantity of heat needed;
Heat capacity is given by the formula;
[tex] Q = mcdt[/tex]
Where;
Q represents the heat capacity or quantity of heat. m represents the mass of an object. c represents the specific heat capacity of water. dt represents the change in temperature.dt = T2 - T1
dt = 200 - 0
dt = 200°C
Substituting the values into the equation, we have;
[tex] Q = 225*0.129*200[/tex]
Q = 5805 Joules.
Therefore, the amount of heat needed is 5805 Joules.
Given values:
Mass, [tex]m = 2250 \ g[/tex]Specific heat capacity, [tex]0.129 \ J/g.^{\circ} C[/tex]Initial temperature, [tex]T_1 = 0.0^{\circ} C[/tex]Final temperature, [tex]T_2 = 200.0^{\circ} C[/tex]then,Change in temperature, [tex]dt = T_2-T_1[/tex][tex]= 200-0[/tex]
[tex]= 200^{\circ} C[/tex]
As we know the formula,
→ Heat capacity, [tex]Q = mcdt[/tex]
By substituting the values, we get
[tex]= 225\times 0.129\times 200[/tex]
[tex]= 5805 \ Joule s[/tex]
Thus the above answer is right.
Learn more about heat here:
https://brainly.com/question/20846683
Which of the following electronic transitions in the oxygen atom will result in light emission?
A.n i= 1⟶nf = 2
B.n i= 1⟶nf =3
C. n i =3⟶n f =2
D. n i =2⟶n f =3
Answer:The answer is C. n i =3⟶n f =2
Explanation: I just take the test, I hope and helps, I know that is late.
Answer:
C. nᵢ = 3 ⟶ nᶠ = 2
Explanation: