Answer:
Molar mass = 27 g/mol
Explanation:
Given data;
Number of moles of Al = 0.2 mol
Mass of Al = 5.4 g
Molar mass of Al = ?
Solution:
Formula:
Number of moles = mass/molar mass
By putting values,
0.2 mol = 5.4 g/ molar mass
Molar mass = 5.4 g/ 0.2 mol
Molar mass = 27 g/mol
A remnant or trace of an organism from the past is called a
Answer:
a fossil
Explanation:
Answer:Fossil
Explanation:A remnant or trace of an organism of a past geologic age, such as a skeleton or leaf imprint, embedded, and preserved in the Earth's crust, usually in stratified rock.
2H₂ + O₂ -> 2H₂O In this equation, write the coefficient numbers
HELP ME PLEASEEEE
Answer:2H₂+ O₂→ 2H₂O the reactants are 2H₂ and O₂ ... if the theoretical yield is 95 g of water after the chemical reaction you may have only 45g of water
i think
Explanation:
Which factor plays the most important role in allowing this reaction to occur?
Sodium bicarbonate (NaHCO3) is commercially known as baking soda. How many grams and atoms of oxygen are there in 15 grams of sodium bicarbonate? The molar mass of NaHCO3 is
84.01 g/mol.
Answer:
3 atoms of O
8.57g
Explanation:
The problem here is to find the mass of oxygen in the compound and the number of atoms of oxygen.
The formula of the compound is:
NaHCO₃;
Here we have:
1 atom of Na
1 atom of H
1 atom of C
3 atoms of O
So there are 3 atoms of O
To find the mass of oxygen , we use the molar mass of oxygen;
Molar mass of oxygen = 16g/mol
Mass of oxygen = [tex]\frac{3(16)}{84.01}[/tex] x 15 = 8.57g
Describe how an adaptation may have allowed giraffes to survive in savanna ecosystems
Why is the use of high-frequency radio waves a beneficial technological advancement
for humans? Explain.
A. They have the best penetration.
B. They carry more information.
C. They travel over longer distances.
D. They do not require mediums to transmit.
I
Answer:
I think It's C
Explanation:
due to higher waves can get easy transfers and receive those signals for most things, such as radios, TVs, phone signals etc etc
The use of high-frequency radio waves, a beneficial technological advancement for humans because they travel over longer distances.
What is frequency ?The frequency of a repeated event is its number of instances per unit of time. In certain cases, it is also referred to as temporal frequency or ordinary frequency to underline differences with spatial and angular frequencies, respectively.
The number of waves that pass a specific place in a predetermined period of time is known as the wave frequency. The hertz (Hz) is the SI unit for wave frequency, where 1 hertz is equivalent to 1 wave crossing a fixed point in 1 second.
The vibrations that created the wave had the same frequency as the wave itself. For instance, you need to move a rope up and down faster to produce a wave with a greater frequency.
Thus, option C is correct.
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5
What substance would do the best job of cleaning pots and
pans?
A
A substance with a pH of 7
B
A substance with a pH of 2
C
A substance with a pH of 4
D
A substance with a pH of 8
Answer:
D . A substance with a pH of 8
Explanation:
pH stands for "Potential for Hydrogen." This is an indicator of a solution's acidity or alkalinity. It is also used to tell which chemicals are great for cleaning.
pH 7 and pH 8 are both considered "neutral pH," thus, solutions with these pH are often used as dishwashing detergents because they do not destroy the surfaces of objects. However, pH 8 is said to be more alkaline in nature. This allows it to destroy the residues, such as fats and oils, in pots and pans. It is the pH of baking soda.
consider an atom that has an electron in an exicted state . the electron falls to a lower energy level . what effects does that have on the electron ?
Answer:
Each time an excited helium atom falls back from an excited state to its ground state or to a lower energy state, it emits a photon of radiation that shows up as this specific line-emission spectrum.
Explanation:
4. Which of the following have mass? Select all that apply.
O A neon-filled tube.
A diamond.
Water in a glass
The helium in a balloon.
Answer:
All except a diamond
Explanation:
The helium in the balloon has mass it fills the space its in.
The neon-filled tube has mass because it takes up space.
Water in a glass has mass because the water is taking up space.
A diamond does not because it does not take up space.
Identify the common name of this free-living organism.
Tubular organism with tentacles surrounding its mouth; a cnidarian
Hydra
SORRY I DON'T KNOW CORRECT BUT
I THOUGHT THATH THIS IS A CATEPILLAR
PLEASE THANKS THIS ANSWER
Which is an empirical formula? C₂H₄ C₃H₆ P₂O₅ P₄O₆
Answer:
C3H8
Propane/Formula
Explanation:
hope this helps
A student noticed that the size of the hot pack becomes bigger when magnesium sulfate reacts with water. She thinks that more atoms are produced that make the hot pack grow bigger. Do you agree? Explain.
Answer:
Disagree with the suggestion based on the hygroscopic nature of anhydrous magnesium sulfate
Explanation:
Magnesium sulfate in the anhydrous form is a drying agent. A drying agent salts of inorganic compounds that has the capability of absorbing water to become hydrated, when placed in the presence of a wet surface or moist air
Anhydrous magnesium sulfate is therefore hygroscopic such that it absorbs water from the atmosphere and becomes hydrated and increases in size as its volume is increased according to the following chemical equation
MgSO₄(s) + 7H₂O(l) → MgSO₄·7H₂O(s)
The molar mass of anhydrous magnesium sulfate = 120.366 g/mol
The molar mass of the heptahydrate = 246.47 g/mol
Therefore, the mass of the magnesium sulfate doubles when it forms the heptahydrate, and the magnesium sulfate grows bigger.
How does the number of molecules in 1 mol of oxygen compare with the number of molecules in 1 mol of nitrogen?
1 mol of oxygen has fewer molecules.
1 mol of oxygen has more molecules.
Each sample has the same number of molecules.
The molecules cannot be compared without knowing the mass.
Answer:
Each sample has the same number of molecules.
Explanation:
Just took the quiz on edge 2021
Taking into account the definition of Avogadro's number, each sample has the same number of molecules.
Avogadro's NumberAvogadro's Number or Avogadro's Constant is called the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance. Its value is 6.023×10²³ particles per mole.
Avogadro's number applies to any substance.
This caseAvogadro's number applies to any substance. This means that the number of molecules in 1 mol of oxygen is equal to the number of molecules in 1 mol of nitrogen.
Finally, the correct answer is the third option: each sample has the same number of molecules.
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A heterogeneous mixture that has very small dispersed particles and stays mixed for a long time is a____. it for science class
What is one possible excited state configuration for fluorine? *
Answer:
Excited State Configuration: 1s^2 2s^2 2p^4 3s^1 are sperated by 13.00 eV.
Which of the following is not a property of most
transition metals?
Answer:
Low melting point
Explanation:
Transition metals have the following properties:
Conductivity (Electrical and Thermal)
Malleability (You can hit it with a hammer to mold it)
High melting point
Answer:
Low melting point
Explanation:
Most transition metals property is high melting point.
3. If 12.5 grams of copper are reacted with excess chlorine gas, then 25.4 grams of
copper (II) chloride are produced. Calculate the theoretical yield and the percent
yield. Cu + Cl2 → CuCl2
Answer:
Percent yield = 99.6%
Theoretical yield = 25.5 g
Explanation:
Given data:
Mass of copper = 12.5 g
Mass of copper(II) chloride produced = 25.4 g
Theoretical yield = ?
Percent yield = ?
Solution:
Chemical equation:
Cu + Cl₂ → CuCl₂
Number of moles of copper:
Number of moles = mass/molar mass
Number of moles = 12.5 g / 63.5 g/mol
Number of moles = 0.19 mol
Now we will compare the moles of copper and copper chloride.
Cu : CuCl₂
1 : 1
0.19 : 0.19
Mass of CuCl₂: Theoretical yield
Mass = number of moles × molar mass
Mass = 0.19 mol × 134.45 g/mol
Mass = 25.5 g
Percent yield:
Percent yield = (actual yield / theoretical yield )×100
Percent yield = ( 25.4 g/ 25.5 g) ×100
Percent yield = 99.6%
Explain, in your own words, what volumic mass is
plss helpp
Answer:
I think that volumic mass is like weight of an object, or like the space it takes up??
Explanation:
Have A Wonderful Day !!
Mg(s) + HCl(aq) −→ MgCl2(aq) + H2(g).
What mass of HCl is consumed by the reaction of 2.28 mol of magnesium?
Answer in units of g
166 g HCl
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
BracketsParenthesisExponentsMultiplicationDivisionAdditionSubtractionLeft to RightChemistry
Stoichiometry
Reading a Periodic TableBalancing EquationsUsing Dimensional AnalysisExplanation:Step 1: Define
[RxN - Unbalanced] Mg (s) + HCl (aq) → MgCl₂ (aq) + H₂ (g)
[RxN - Balanced] Mg (s) + 2HCl (aq) → MgCl₂ (aq) + H₂ (g)
[Given] 2.28 mol Mg (s)
Step 2: Identify Conversions
[RxN] 1 mol Mg = 2 mol HCl
Molar Mass of H - 1.01 g/mol
Molar Mass of Cl - 35.45 g/mol
Molar Mass of HCl - 1.01 + 35.45 = 36.46 g/mol
Step 3: Stoichiometry
Set up: [tex]\displaystyle 2.28 \ mol \ Mg(\frac{2 \ mol \ HCl}{1 \ mol \ Mg})(\frac{36.46 \ g \ HCl}{1 \ mol \ HCl})[/tex]Multiply: [tex]\displaystyle 166.258 \ g \ HCl[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
166.258 g HCl ≈ 166 g HCl
the bond between which two atoms is most polar
Answer:
bond
Explanation:
It is a polar bond because it is when two atoms bond
Brianna explains to Logan the role of plants in the carbon cycle. Choose the sentence(s) that she includes in her explanation. Select all that apply.
A.
Animals get carbon from plants.
B.
Plants take carbon from the soil.
C.
Photosynthesis uses carbon monoxide.
D.
Animals take carbon from the atmosphere.
E.
Plants take carbon from the atmosphere.
Answer:
E) Plants take carbon from the atmosphere
Explanation:
Plants are a vital part in keeping the air clean. They take in CO2, H2O, and sunlight to start processing photosynthesis. The carbon taken in by the plant still remains with it after it dies, thus, fossil fuels.
Answer:
e is correct
Explanation:
Which of the following is one part of a chemical formula for a molecule?
A) A number that shows the total number of chemical bonds
B) Numbers that show how many atoms of each element are in the molecule
C) A number showing the atomic masses of each element
D) A Lewis dot diagram for the molecule
An ____,or an element located in group 7A, will form a salt when reacted with a metal atom.
A. Alkali metal
B. Halogen
C. Noble gas
D. Transition metal
Answer:
B. Halogen
Explanation:
Halogens are the family of chemical elements found in the group VIIA of the periodic table which means they possess seven (7) outer electrons. Some examples of halogens are Fluorine (F), Iodine (I), Bromine (Br), and Chlorine (Cl).
A halogen, or an element located in group 7A, will form a salt when reacted with a metal atom.
For example, when Chlorine reacts with Sodium it would form a salt known as Sodium Chloride.
Na + Cl ----> NaCl
how many element are there on the periodic table?
Answer:118
Explanation: it’s right
Answer:
118 elements
Hope that helps
How many moles are there in 2.43e+21 molecules of carbon dioxide?
Moles of Carbon dioxide : n = 4.037 x 10⁻³
Further explanationGiven
2.43 x 10²¹ molecules of Carbon dioxide
Required
Moles
Solution
1 mol = 6.02 x `10²³ particles(molcules, atoms, ions)
Can be formulated :
N = n x No
n = moles
No = Avogadro's number 6.02 x `10²³
moles of Carbondioxide :
n = N/No
n = 2.43 x 10²¹ / 6.02 x `10²³
n = 4.037 x 10⁻³
1) Which electrons are involved in bonding between atoms?|
Answer:
VALENCE ELECTRONS are involved in the bonding of atoms
Explanation:
Hope that helps
(Help if you know) What is one way land helps reduce the force of a hurricane as it moves inland?
A) land stabilizes the sediment forced on shore
B) Land filters the water forced up from the sea by the wind
C) Land acts as a bumpy surface that absorbs wind power
D) land absorbs the rainwater
1.004 mol Arsenic is how many atoms?
Answer: [tex]6.047\times 10^{23}[/tex] atoms in 1.004 mol of arsenic
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
To calculate the atoms, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given atoms}}{\text {avogadro's number}}[/tex]
[tex]1.004=\frac{x}{6.023\times 10^{23}}[/tex]
[tex]x=1.004\times 6.023\times 10^{23}=6.047\times 10^{23}[/tex]
Thus there are [tex]6.047\times 10^{23}[/tex] atoms in 1.004 mol of arsenic
Water, H2O, frequently forms Hydrogen Bonds with other non metal atoms.
Why does water do this?
A: the Oxygen has a partial negative charge which attracts atoms and molecules that have a position or partial positive charge
B: The Hydrogen has a partial negative charge which attracts atoms and molecules that have a positive or partial positive charge
C: Because Oxygen is extremely electronegative it attracts atoms and molecules with a negative or partial negative charge
D: Because Hydrogen has a very low electronegative rating it attracts atoms and molecules with a positive or partial positive charge
Answer:
Opposite charges attract one another. The slight positive charges on the hydrogen atoms in a water molecule attract the slight negative charges on the oxygen atoms of other water molecules. This tiny force of attraction is called a hydrogen bond.
Considering the definition of hydrogen bond, the correct answer is option A: he Oxygen has a partial negative charge which attracts atoms and molecules that have a position or partial positive charge.
In hydrogen bonds, a molecule that presents hydrogen interacts with another that presents an atom with high electronegativity, such as oxygen, fluorine or nitrogen (O, F, N). In this way, between the hydrogen, which has a low electronegativity and the electronegative atom, an interaction is established, due to their opposite charges.
On the other hand, electronegativity is the ability of an atom to attract shared electrons in a covalent bond.
In the case of water, because oxygen is more electronegative than hydrogen, electrons, which have a negative charge, are more likely to be closer to the oxygen atom than to the hydrogen atom, which causes each hydrogen atom to have a positive charge is called a positive partial charge, and that of oxygen, a negative charge, since it has the electrons closer together.
In summary, the correct answer is option A: he Oxygen has a partial negative charge which attracts atoms and molecules that have a position or partial positive charge.
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https://brainly.com/question/15698308https://brainly.com/question/14210785?referrer=searchResultshttps://brainly.com/question/4542860?referrer=searchResultsWhich of the following statements is true about the relationship between atoms and molecules? A. Most atoms are bonded together to make a molecule. B. An atom can be seen by scientists, but a molecule cannot. C. Atoms and molecules are the same and have no differences.
Answer:
I believe the answer is A. molecules are larger than atoms so they should be visible and atoms and molecules are indeed different
To see the number of atoms of an element in a given molecule we need to multiply stoichiometry to the number that is written on the foot of the element that is stoichiometry. Therefore, the correct option is option A.
What is atom?
Atom is the smallest particle of any element, molecule or compound. Atom can not be further divided. Atoms contains nucleus in its center and electron that revolve around the atom in fixed orbit.
In the nucleus, proton and neutron are present. Electron has -1 charge while proton has +1 charge. Neutron is neutral that is it has no charge. So overall the charge of nucleus is due to only proton, not by neutron. Most atoms are bonded together to make a molecule. Molecules combine to form compounds.
Therefore, the correct option is option A.
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