Answer:
Chemical symbols refer to chemical elements only. They do not necessarily refer to atoms of that element, but also to ions.
Explanation:
Halfnium has three isotopes; 74% Hf-180, 17% Hf -176, and 9 % Hf- 177. Calculate the mass of Halfnium.
Answer:
179.05 g/mol
Explanation:
simple called the percentage of the molecular mass of each isotope and add them together. their sum is the mass of Halfnium.
thus
Hf --- 74/100 × 180 = 133.2
Hf --- 17/100 × 176 = 29.92
Hf --- 9/100 × 177 = 15.93
total mass = 133.2+29.92+15.93
= 179.05 g/mol
When converting an “ordinary” number that is greater than 1 to scientific notation, how many non-zero digits are to the LEFT of the decimal point when you are finished?
Answer: 0 I think
Explanation:
pretty sure its zero because i learned it last year but im in middle school so you might want to look it up.
Please help
What subatomic particle is not important when calculating the atomic mass of an atom
Answer:
Electrons
Explanation:
This is because electrons barely contribute to the mass so only protons and neutrons are added.
Element X
Is a Solid at room temperature
Is a metalloid and semiconductor of heat and
electricity
Reacts with Oxygen to form XO2,
compounds and with chlorine to form XCI4,
compounds
Has an average atomic mass that is 2.34
times greater than the standard for atomic
mass(Carbon-12)
When does carbon dioxide absorb the most heat energy?
during freezing
during deposition
during sublimation
during condensation
Answer:
during sublimation
Explanation:
just took the test
Consider the reaction of zinc metal with hydrochloric acid:
Zn(s) + 2 HCl(aq) → ZnCl2(aq) + H2(g).
If 29.39 × 1024 atoms of zinc completely reacted with hydrochloric acid, how many moles of hydrochloric acid must have reacted?
Do NOT include units in your entry. Report your answer with 3 SFs.
______________________ moles of HCl
Answer:
6.054×10²⁵
Explanation:
1)find number of moles of zinc
2)multiply the mole of zinc with 2
3)use the formula mol = number of particle/ avogadro constant
Total, 97.64 moles of hydrochloric acid (HCl) must have reacted.
To determine the number of moles of hydrochloric acid (HCl) that reacted, we first need to find the molar ratio between zinc (Zn) and hydrochloric acid (HCl) from the balanced chemical equation:
Zn(s) + 2 HCl(aq) → ZnCl₂(aq) + H₂(g)
From the equation, we see that 1 mole of Zn will reacts with 2 moles of HCl.
Given that 29.39 × 10²⁴ atoms of zinc reacted, we need to convert this quantity to moles. We can do this by using Avogadro's number:
1 mole of any substance = 6.022 × 10²³ atoms
Number of moles of zinc reacted = (29.39 × 10²⁴ atoms) / (6.022 × 10²³ atoms/mol)
Number of moles of zinc reacted ≈ 48.82 moles (rounded to 3 significant figures)
Now, using the molar ratio from the balanced equation, we can determine the number of moles of hydrochloric acid (HCl) that reacted:
Number of moles of HCl reacted = 2 × Number of moles of zinc reacted
Number of moles of HCl reacted ≈ 2 × 48.82 moles
≈ 97.64 moles
Therefore, approximately 97.64 moles of hydrochloric acid (HCl) must have reacted.
To know more about hydrochloric acid here
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Calcium reacts with sulfur forming calcium sulfide. What is the theoretical yield (g) of CaS(s) that could be prepared from 7.19 g of Ca(s) and 2.67 g of sulfur(s)? Enter your answer with two decimal places. Do not type units with your answer.
Answer:
The theoretical yield of CaS is 6.01 g.
Explanation:
The balanced reaction is given as:
[tex]Ca+S\rightarrow CaS[/tex]
The molar mass of Ca and S is 40.08 and 32.065 g/mol respectively.
Number of moles = [tex]\frac{Mass}{Molar Mass}[/tex]
So, 7.19 g of Ca contains [tex](\frac{7.19}{40.08})[/tex] mol of Ca or 0.179 mol of Ca
Also, 2.67 g of S contains [tex](\frac{2.67}{32.065})[/tex] mol of S or 0.0833 mol of S
According to the balanced equation:
1 mol of Ca produces 1 mol of CaS
So, 0.179 mol of Ca produces 0.179 mol of CaS
According to the balanced equation:
1 mol of S produces 1 mol of CaS
So, 0.0833 mol of S produces 0.0833 mol of CaS
As the least number of mol of CaS (product) is produced from S , therefore, S is the limiting reactant.
So, thoretically, 0.0833 mol of CaS is produced.
The molar mass of CaS is 72.143 g/mol.
So, the mass of 0.0833 mol of CaS is [tex](0.0833\times 72.143)[/tex] g or 6.01 g
Hence, the theoretical yield of CaS is 6.01 g.
An element that reacts with oxygen to form XO2 compounds and with chlorine to form XCI4 compounds???
Answer:
An element X reacts with oxygen to form XO
and with chlorine to form XCl
. XO
is a white solid that melts at high temperatures (above 1000 degrees C). Under usual conditions, XCl
is a colorless liquid with a boiling point of 58 degrees C.
Explanation:
What is the predictable process in which one element type is converted into a new form?Immersive Reader
(10 Points)
A. Law of Superposition
B. Igneous formation
C. Fossil formation
D. Radioactive decay
Answer:
Radioactive decay
Explanation:
Answer:
D. Radioactive decay
Explanation:
Answer each of the following questions with increases, decreases, or does not change.
a) If the intermolecular forces in a liquid increase, the normal boiling point of the liquid increases .
b) If the intermolecular forces in a liquid increase, the vapor pressure of the liquid does not change .
c) If the surface area of a liquid increases, the vapor pressure increases .
d) If the temperature of a liquid decreases, the equilibrium vapor pressure increases .
Drag and drop your selection from the following list to complete the answer:
does not change decreases increases
Answer:
1) Increases
2) decreases
3) increases
4) decreases
Explanation:
When the intermolecular forces in a liquid increases, the greater vapour pressure of the liquid decreases accordingly.
Since the vapour pressure is proportional to temperature, as temperature increases, the vapour pressure increases alongside.
As intermolecular forces increases, the boiling point increases accordingly since more energy is required to break intermolecular bonds.
Lastly, the greater the surface area, tell greater the vapour pressure since more liquid surface area is now available.
How many moles of methane are produced when 48.1 moles of carbon dioxide gas react with excess hydrogen gas?
Which item has the most thermal energy?
A. 1 kg boiling water
B. 1 kg ice
C. 1 kg hot water just below the boiling point
D. 1 kg cold water
Answer:
1L of hot water just below the Boling point
Explanation:
asking questions is best to learn please ask more questions
Answer:
its 1kg of boiling water
Explanation:
a 108ml sampl of gas has a mass of 77.96mg at a pressure of 1140mmhg and temperature of 183°c .what is the molar mass of the gas ?
Answer:
146.85 g/mol
Explanation:
PV=nRT
n=mass/molar mass
covert from mmhg to atm = 0.184 atm
convert from ml to L= 0.108 L
convert from degree C to K= 456.15 K
convert from mg to g= 0.07796g
then rearrange the formula:
n=PV/RT
=(0.184)(0.108)/(0.08206)(456.15)
n= 5.308*10^(-4)
rearrange the n formula interms of molar mass:
Molar mass= mass/n
=0.07796/(5.308*10^-4)
molar mass= 146.85g/mol
Answer:
Molar mass = 20 g/mol
Explanation:
Given data:
Volume of gas = 108 mL
Mass of gas = 77.96 mg (77.96/1000 = 0.08 g)
Pressure of gas = 1140 mmHg
Temperature of gas = 183°C
Molar mass of gas = ?
Solution:
First of all we will calculate the number of moles of gas.
PV = nRT
R = general gas constant = 0.0821 atm.L/ mol.K
Now we will convert the units and then we will put the values in formula.
Volume of gas = 108 mL× 1 L/1000 mL= 0.108 L
Pressure of gas = 1140 mmHg× 1 atm / 760 mmHg = 1.5 atm
Temperature of gas = 183+273 = 456 K
PV = nRT
1.5 atm ×0.108 L = n × 0.0821 atm.L/ mol.K ×456 K
0.162 atm.L = n ×37.44 atm.L/ mol
n = 0.162 atm.L/37.44 atm.L/ mol
n = 0.004 mol
Molar mass of gas:
Number of moles = mass/molar mass
0.004 mol = 0.08 g / molar mass
Molar mass = 0.08 g /0.004 mol
Molar mass = 20 g/mol
Pls help, and fast plsssssssss
Answer:
The cell on the left is animal, The cell on the right is a plant cell.
Explanation:
1: cell membrane
2: chloroplast
3: cell wall
4: vacuole
5: mitochondria
6:nucleus
7: lysosome
8: cytoplasm
Things to remember, only plant cells have cell walls. Plant cells are the only ones that have chloroplast.
The energy associated with the motion and position of an object is called a.kinetic energy
b.potential energy
c.gravitational potential energy d.mechanical energy
Answer: The answer is D.
Explanation:
The form of energy associated with the motion, position, or shape of an object is called mechanical energy. An object's mechanical energy is a combination of its potential energy and its kinetic energy. The basketball has both potential energy and kinetic energy.
Hope this helps!
The equilibrium constant for A + 2B → 3C is 2.1 * 10^-6
Determine the equilibrium constant for 2A + 4B → 6C.
a- 4.2 * 10^-6
b- 4.4 * 10^-12
c- 2.3 *10^11
d- 1.8 *10^-11
e- None of these
Answer:
b- 4.4 * 10^-12.
Explanation:
Hello.
In this case, as the reaction:
A + 2B → 3C
Has an equilibrium expression of:
[tex]K_1=\frac{[C]^3}{[A][B]^2}=2.1x10^{-6}[/tex]
If we analyze the reaction:
2A + 4B → 6C
Which is twice the initial one, the equilibrium expression is:
[tex]K_2=\frac{[C]^6}{[A]^2[B]^4}[/tex]
It means that the equilibrium constant of the second reaction is equal to the equilibrium constant of the first reaction powered to second power:
[tex]K_2=K_1^2[/tex]
Thus, the equilibrium constant of the second reaction turns out:
[tex]K_2=(2.1 * 10^{-6})^2\\\\K_2=4.4x10^{-12}[/tex]
Therefore, the answer is b- 4.4 * 10^-12.
Best regards.
Radiation is transferring thermal energy by=
circulating fluids
touching/physical contact
electromagnetic waves
none of the above
which one is correct
Please give just give me the first column of answers! I can do the rest. Just can’t find any.
Answer:
h20
Explanation:
which describes bedrock?
a. consist of a solid rock
b.lies directly above the soil layer
c, does not contain weathered rock
d. forms from decomposed material
2.
(3x – 4y = -10
(6x + 3y = –42
SOLUTION:
Answer:
Is like for solving for the solution for both equations??
4.5 tons → lbs
4.5 tons equals how many pounds
Answer:
9000 pounds
Explanation:
9000 pounds
Answer: 9000 lbs.
Explanation: 4.5 tons = 9000 pounds.
sulphur is non metal why
Answer:
Sulfur is characterized as a non-metal because it is consistent with the 3 physical properties listed for nonmetals. It is a poor conductor of heat and electricity because the electrons are not free to move.
Explanation:
which of the following Ph levels would indicate the weakest base?
15
8
6
2
Answer:
8
Explanation:
7 is neutral any anything above it is basic and anything below is acidic which means 8 would be the lowest base
Answer:
The pH of a weak base falls somewhere between 7 and 10.
Explanation:
Like weak acids, weak bases do not undergo complete dissociation; instead, their ionization is a two-way reaction with a definite equilibrium point
True or False: Particles that are moving faster have a higher temperature
Answer:
true
Explanation:
I'm not sure why cause I dont know how to explain but it's TRUE
Answer:
True
Explanation:
The particles moving faster in a substance the hotter it gets.
Which accurately represents these building blocks of matter from the smallest to the largest?
atom -- molecule or compound
O molecule -- atom - element
compound - molecule -- element
molecule atom or element
Answer:
A - Atom ---> molecule or compound.
Given the mass of carbon on the periodic table (12.01 amu), which isotope do you think is the most abundant? Explain WHY in complete sentences. *
Answer:
Carbon-12
Explanation:
Carbon-12 is a carbon with 6 protons and 6 neutrons. Since the AMU for an element is calculated by averaging all naturally occurring isotopes, we can see that 12 in the most abundant. (Since 12.01 is very close to 12, the only reason it is not exactly 12 is because there are other isotopes like carbon-13 or carbon-14 but in low amounts)
Calculate the atomic mass of nitrogen if the two common isotopes of nitrogen have masses
of 14.003 amu (99.63% abundance) and 15.000 amu (0.37% abundance).
What are the conjugate base and conjugate acid for HSO4−? What is the term used to describe species that can behave as either an acid or a base, depending on the chemical environment?
Answer:
Conjugate acid- H^+
Conjugate base- SO4^2-
Terminology- Amphoteric
Explanation:
Consider the equilibrum shown below;
HSO4^-(aq)<-------> H^+(aq) + SO4^2-(aq)
Hence, When HSO4^- is dissolved in aqueous solution, it's conjugate acid is H^+ and it's conjugate base is SO4^2- as shown in the equation above.
If a substance behaves both as an acid and as a base, then the substance is Amphoteric in nature.
The conjugate acid [tex]H^+[/tex]and base [tex]SO4^2-[/tex] and the term would be Amphoteric.
Conjugate acid-
What is Amphoteric?Amphoteric is described as the term employed to denote a substance that possesses the characteristics of both an acid, as well as, a base.
Given equilibrium:
[tex]HSO4^-(aq)[/tex] → [tex]H^+(aq) + SO4^2-(aq)[/tex]
Therefore, the dissolution of [tex]HSO4^-[/tex] in water leads to the display acid that is conjugate [tex]H^+[/tex] and the conugate base [tex]SO4^2-[/tex].
In case, the properties of both are reflected, it shows amphoteric nature.
Learn more about "Acid" here:
brainly.com/question/26083032
10. Which of the following is NOT correctly matched?
A. Salt: Na and C: Element
B. Water: H and O: Corapound
C. Carbon dioxside: C and O: Compound
D. Magnesium chloride: Mg and C: Compound
Answer:
A. because salt : Na and Cl, not C
A sample of propane, C3H8, contains 13.8 moles of carbon atoms. How many total moles of atoms does the sample contain
Answer:
[tex]Total = 50.6\ moles[/tex]
Explanation:
Given
[tex]Propane = C_3H_8[/tex]
Represent Carbon with C and Hydrogen with H
[tex]C = 13.8[/tex]
Required
Determine the total moles
First, we need to represent propane as a ratio
[tex]C_3H_8[/tex] implies
[tex]C:H = 3:8[/tex]
So, we're to first solve for H when [tex]C = 13.8[/tex]
Substitute 13.8 for C
[tex]13.8 : H = 3 : 8[/tex]
Convert to fraction
[tex]\frac{13.8}{H} = \frac{3}{8}[/tex]
Cross Multiply
[tex]3 * H = 13.8 * 8[/tex]
[tex]3 H = 110.4[/tex]
Solve for H
[tex]H = 110.4/3[/tex]
[tex]H = 36.8[/tex]
So, when
[tex]C = 13.8[/tex]
[tex]H = 36.8[/tex]
[tex]Total = C + H[/tex]
[tex]Total = 13.8 + 36.8[/tex]
[tex]Total = 50.6\ moles[/tex]