Answer:
2CO >>> 2C + O2
........
Determine the number of moles in 5.25x1024 formula units if lead (IV) oxide.
Answer:
8.72 mol PbO₂
General Formulas and Concepts:
Chemistry - Atomic Structure
Using Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Explanation:
Step 1: Define
5.25 × 10²⁴ formula units PbO₂
Step 2: Identify Conversions
Avogadro's Number
Step 3: Convert
[tex]5.25 \cdot 10^{24} \ formula \ units \ PbO_2(\frac{1 \ mol \ PbO_2}{6.022 \cdot 10^{23} \ formula \ units \ PbO_2} )[/tex] = 8.71803 mol PbO₂
Step 4: Check
We are given 3 sig figs. Follow sig fig rules and round.
8.71803 mol PbO₂ ≈ 8.72 mol PbO₂
PLS PLS PLS HELP I WILL MARK YOU BRAINLYEST PLS
Answer:
A: Endoplasmic reticulum
B: Chroloplast
C: Mitochondrion
D: Cytoplasm
E: Cell wall
Explanation:
What is the advantage of using Microsoft Excel to create a graph, as opposed to pen and paper?
Chemistry class I NEED HELP FAST
Answer:
the advantage of using Microsoft Excel to create a graph, as opposed to pen and paper is it will help you get the right answer
Explanation:
can you pls help me with this question
Answer:
probably c
Explanation:
Answer: I feel like the correct answer is choice C but I really don’t know how to explain it..
Solid carbon dioxide (CO2), also known as dry
ice, changes into a gas at room temperature. An
image of this change can be seen below.
Is this an example of a physical change? Why
or why not?
Answer:
yes
Explanation:
yes because the ice changes forms physically and can be changed back. not 100% sure tho
Answer:
shiii ion even know like i cant even tell u tha
Explanation:
bro 2 of my bruddas got locked up 2 days ago one of em got shot before the cops took him
What is the concentration of a stock solution if 20 mL was used to make 400 mL of a 1.44
M solution?
30 M
40 M
50 M
5M
Given :
Volume of stock solution, [tex]V_s = 20\ mL[/tex].
Volume of diluted solution, [tex]V_d = 400 \ mL[/tex].
Molarity of diluted solution, [tex]M_d = 1.44\ M[/tex].
To Find :
The concentration of the stock solution.
Solution :
We know, dilution factor is given by :
[tex]D.F=\dfrac{V_ {diluted}}{V_{stock}}[/tex] ....1)
and [tex]D.F= \dfrac{M_{stock}}{M_{diluted}}[/tex] ....2)
Putting volume in above equation, we get :
D.F = 400/20
D.F = 20
Putting value of D.F in equation 2) we get :
[tex]\dfrac{M_{stock}}{M_{diluted}} = 20\\\\M_{stock} = 20\times 1.44\\\\M_{stock} =28.8\ M[/tex]
The concentration of stock solution is nearest to 30 M.
Therefore, the correct option is 1) 30 M.
Fill in the blanks. A person would weight more on Neptune than on planet blank
because
blank
A person would weigh more on Neptune than on planet earth because the gravitational field strength is stronger on Neptune.
A person would weight more on Neptune than on planet earth because the gravitational force in neptune is more.
What is gravitational force?Gravitational forces is a kind of attraction force which is present between two objects of masses.
Gravitational force on the neptune planet is more as compared to the gravitational force on the earth. So the mass of any object present in the neptune is more than the earth.
Hence a person would weight more on Neptune than on planet earth because gravitatinal force in neptune is more.
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What goes in photosynthesis and what comes out of photosynthesis?
Answer:
Carbon dioxide goes in and oxogen comes out
P.S. Sunlight needed for this process to work
Explanation:
How many moles are in 2.91 x 10^22 molecules of Helium?
Answer:
0.048 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\[/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
[tex]n = \frac{2.91 \times {10}^{22} }{6.02 \times {10}^{23} } \\ = 0.048338...[/tex]
We have the final answer as
0.048 molesHope this helps you
PLEASE HELP!!!!
7. According to Mohs Hardness scale, which of these groups of minerals can scratch fluorite? А. B. talc, calcite, and apatite calcite, quartz, and topaz apatite, orthoclase, and corundum diamond, gypsum, and quartz C.
Answer:
B
IS THE CORRECT ANSWER
Choose the molecule with the strongest internal bond, (intra-, not intermolecular bond)
Answer:
A
Explanation:
The molecule with the strongest intramolecular bond is HF. Hydrogen fluoride is the answer due to the strong and highly electronegative nature of Fluorine.
Fluorine is the most electronegative element in nature. When it combines with other substances, due to its electronegative property, it draws most of the electrons closest to itself in the bond. This tendency and ability makes the shared electrons closer the fluorine in the bond. The strong polarization that ensues confers a very strong covalent bond pair on the bond formed.The molecule with the strongest internal bond is HF and the correct option is option A.
An intramolecular bond, also known as a chemical bond, refers to the attractive forces that hold atoms together within a molecule. It involves the sharing, transferring, or rearrangement of electrons between atoms to achieve a more stable configuration.
There are three primary types of intramolecular bonds:
Covalent Bond: In a covalent bond, atoms share electrons to achieve a more stable electron configuration. This bond is formed between nonmetal atoms.Ionic Bond: An ionic bond is formed when there is a complete transfer of electrons from one atom to another. It involves the attraction between positively and negatively charged ions. Ionic bonds typically occur between a metal and a nonmetal.Metallic Bond: Metallic bonding occurs in metals and is characterized by a "sea of electrons" in which the valence electrons are delocalized and free to move within the metal lattice. This allows metals to conduct electricity and exhibit other unique properties.Thus, the ideal selection is option A.
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What happens to alpha particles as they get closer to the gold nucleus?
Answer:
Initially the alpha particle has only kinetic energy EK. As it approaches the gold nucleus it suffers repulsion by the 79 protons within that nucleus. Its kinetic energy changes into electric potential energy EP.
Plz help already late in turning it in
Which is the formula for iodine tribromide?
IBr
IB3
IBr3
I3Br
Answer:
the answer is c IBr3
Explanation:
The chemical formula for iodine tribromide is IBr₃ as it has 1 iodine and 3 bromine atoms.
What is chemical formula?
Chemical formula is a way of representing the number of atoms present in a compound or molecule.It is written with the help of symbols of elements. It also makes use of brackets and subscripts.
Subscripts are used to denote number of atoms of each element and brackets indicate presence of group of atoms. Chemical formula does not contain words. Chemical formula in the simplest form is called empirical formula.
It is not the same as structural formula and does not have any information regarding structure.It does not provide any information regarding structure of molecule as obtained in structural formula.
There are four types of chemical formula:
1)empirical formula
2) structural formula
3)condensed formula
4)molecular formula
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1. An element is defined by the number of:
Electrons
Protons
Neutrons
Chemical Bonds
lons
Answer:
The correct answer for this question would be B) Protons
Explanation:
I got it right on my test (Can I have brainlyest)
two negative charges are placed near each other. what happens between the charges
Answer:
repulsion
Explanation:
Answer:
Explanation:
In contrast to the attractive force between two objects with opposite charges, two objects that are of like charge will repel each other. ... Similarly, a negatively charged object will exert a repulsive force upon a second negatively charged object. Objects with like charge repel each other.
how does an electron emit light?
Answer:
by moving between defined energy levels
Help plz 15 pointsss
How much energy is required to vaporize 14.27 grams of water at its
boiling point? *
Energy required to vaporize : 32.3 kJ
Further explanationThe heat to change the phase can be formulated :
Q = mLf (melting/freezing)
Q = mLv (vaporization/condensation)
Lf=latent heat of fusion
Lv=latent heat of vaporization
Mass of water = 14.27 g
Latent heat of vaporization ( boiling point of 100 ºC) : 2260 J/g
Energy required :
[tex]\tt Q=m.Lv\\\\Q=14.27\times 2260\\\\Q=32250.2~J\approx 32.3~kJ[/tex]
Find the percent of water in Zn3(PO4)2 x 7H2O
Answer:
24.66%
Explanation:
To find the percent of water (H2O) in the following compound: Zn3(PO4)2. 7H2O
The atomic mass of the elements are as follows:
Zn = 65g/mol
P = 31g/mol
O = 16g/mol
H = 1g/mol
Hence, molar mass of the compound is as follows:
65(3) + {31 + 16(4)} 2 + 7{1(2) + 16}
195 + 95(2) + 7(18)
195 + 190 + 126
511g/mol
Molar mass of 7H2O
= 7(18)
= 126g/mol
Hence, the percent of H2O in the compound is:
Molar Mass of 7H2O/molar mass of compound × 100
= 126/511 × 100
= 0.2466 × 100
= 24.66%
Much of the earth’s heat is retained in the
crust.
wind.
oceans.
mountains.
WILL GIVE BRAINLIEST (major help!!! need now!!!) David observed properties of four different compounds, only one of which is an ionic compound. His observations are shown in the chart.
A 2-column table with 4 rows. The first column labeled compound has entries W, X, Y, Z. The second column labeled observations has entries is a hard solid, melts at 44 degrees C, has a molecular structure; is a brittle solid, does not conduct electricity in water, has a crystal structure; is a hard solid, conducts electricity, has a molecular structure; is a brittle solid, melts at 801 degrees C, has a crystal structure.
Which is most likely the ionic compound?
W
X
Y
Z
Answer:
B. X
Explanation:
Answer:
The answer is D
Explanation:
Wave W is being diffracted, Wave X is being reflected, and waves Y and Z are being refracted.
Agree or disagree
one rotation of the earth occurs everyday or 24 hours
Answer:
Agree
Explanation:
The rotation of earth happens about once every 24 hours.
How many grams of CaCI2 (molar mass = 111 g/mol) are needed to prepare 100.mL of 0.100 M CI-(aq) ions?
a.) 0.555 g
b.) 1.11 g
c.) 2.22 g
d.) 5.55 g
I will mark as brainliest if you give the correct answer (brief explanation only, no worries)
Answer:
a
Explanation:
Because that is the answer
____ Ca3(PO4)2(s) + ____ H3PO4(l) → ____ Ca(H2PO4)2(s) When the equation above is balanced and all coefficients are reduced to lowest whole-number terms, what is the coefficient for H3PO4(l)
The equation can be balanced using suitable integers multiplied either side and can be written as follows:
[tex]\rm Ca_{3} (PO_{4})_{2} + 4 H_{3}PO_{4} \rightarrow 3 Ca (H_{2}PO_{4})_{2}[/tex]
Thus the coefficient of H₃PO₄ is 4.
What is balanced reaction?A balanced chemical equation of a reaction represents all the reactants and products in the perfect stoichiometric ratios where, the number of each element have to be equal in both sides.
The given reaction is an example of combination reaction. The equation can be balanced by equating the number of calcium in the product side by multiplying with 3 and then making the phosphate group also balanced by multiplying by 4 with H₃PO₄.
Thus, the balanced chemical equation written above contains 3 calcium on both side and equal number of phosphate group (6) as well as hydrogens on both side where, the coefficient of H₃PO₄ is 4
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12) Which model of the atom is thought to be true?
a. Protons, electrons, and neutrons are evenly distributed throughout the volume of
the atom.
b. The nucleus is made of protons, electrons, and neutrons.
c. Electrons are distributed around the nucleus and occupy almost all the volume of
the atom.
d. The nucleus is made of electrons and protons.
Answer:
B
Explanation:
The neucles is surrounded by electrons. Electrons occupy most of the volume of the atom.
Atomic Model:
Atoms are the smallest unit of elements, which form bonds with others. In an atom, electrons revolve around the nucleus.
The nucleus is composed of positively charged protons and neutrons. The nucleus occupies a very small part of the atom.
Electrons are negatively charged particles, they are found around the nucleus and occupy most of the part of the atom.
Therefore, The neucles is surrounded by electrons. Electrons occupy most of the volume of the atom.
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Can someone define these for me
Answer:
These are all in order....
Explanation:
- closed system usually absorbs thermal energy from its surroundings, which is heat transfer into the system
- a solute is a substance dissolved in another substance, known as a solvent
- A solvent is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid
- a liquid mixture in which the minor component (the solute) is uniformly distributed within the major component (the solvent)
- a nuclear reaction in which a heavy nucleus splits spontaneously or on impact with another particle, with the release of energy
- a nuclear reaction in which atomic nuclei of low atomic number fuse to form a heavier nucleus with the release of energy.
- Half-life is the time required for a quantity to reduce to half of its initial value
- the determination of the age or date of organic matter from the relative proportions of the carbon isotopes carbon-12 and carbon-14 that it contains. The ratio between them changes as radioactive carbon-14 decays and is not replaced by exchange with the atmosphere.
- any system closed to all transfers of matter and energy, the mass of the system must remain constant over time, as the system's mass cannot change, so quantity can neither be added nor be removed
What is the hybridization of the carbon in the HCN molecule?
Why do you see different stars in spring’s night sky than in fall’s night sky? Explain.
Answer:
If observed through the year, the constellations shift gradually to the west. This is caused by Earth's orbit around our Sun. In the summer, viewers are looking in a different direction in space at night than they are during the winter.
Explanation:
Answer:
there it the fact that the earthisspinningand so the starsare staying still and we are spinning
Please help me #6!!!!!!!!