What is atomic mass? the mass of the atom based on the mass of an atom of hydrogen-1 the mass of an atom based on the mass of an atom of carbon-12 the mass of the atom based on the mass of an atom of oxygen-16 the mass of an atom based on the number of electrons

Answers

Answer 1

Answer:

The mass of an atom based on the mass of an atom of carbon-12

Explanation:


Related Questions

que es y que define a los elementos quimicos

Answers

Un elemento químico, o un elemento, se define como un material que no puede descomponerse ni transformarse en otra sustancia por medios químicos. Cada elemento se identifica según la cantidad de protones que tiene en su núcleo atómico. Se puede crear un nuevo elemento agregando más protones a un átomo.

_________

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Question 2
20 pts
What types of elements make up salt and what type of compound is it?
nonmetals only and covalent
metals only and ionic
metals and nonmetals and ionic

Answers

metals only and ionic
NaCl

This is metal (Na) and nonmetal (Cl)

This makes it ionic!!!

methane is called an organic compound why​

Answers

Answer:

Explanation:

1) Organic compounds always contain only p-block elements (Groups III-VII), at least one of which must be carbon. 2) Organic compounds almost always contain one or more C-H bonds. ... Thus, all bonds are typically covalent in organic compounds. Methane (CH4) is the prototypical organic molecule.

Methane contains carbon, forming covalent bonds, and is found in living organisms, making it an organic compound.

Methane (CH₄) is considered an organic compound due to its molecular structure and occurrence in living organisms. Organic compounds are primarily composed of carbon atoms covalently bonded to hydrogen and often other elements like oxygen, nitrogen, sulfur, and more.

Methane consists of one carbon atom bonded to four hydrogen atoms through covalent bonds. Carbon's unique ability to form stable covalent bonds with other elements, including itself, leads to the vast diversity of organic molecules found in living organisms.

Methane is a crucial component of natural gas and is produced by various biological and geological processes. It is present in the digestive systems of animals, formed during decomposition, and plays a role in carbon and energy cycles.

Its prevalence in living systems and its molecular structure classify methane as an organic compound, reflecting the foundational principles of organic chemistry.

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The complete question is :

Methane is called an organic compound why​?

In an experiment trying to dissolve sugar in water, a person boils water in a pot on the stove and then puts the water and the sugar in a cup. That person times how long it takes to dissolve the sugar.

Answers

According to the concept of solubility, boiling water and then adding sugar to it will take longer time to dissolve than adding water and sugar together to boil as thermal energy requires to dissolve sugar will be less.

What is solubility?

Solubility is defined as the ability of a substance which is basically solute to form a solution with another substance. There is an extent to which a substance is soluble in a particular solvent. This is generally measured as the concentration of a solute present in a saturated solution.

The solubility mainly depends on the composition of solute and solvent ,its pH and presence of other dissolved substance. It is also dependent on temperature and pressure which is maintained.Concept of solubility is not valid for chemical reactions which are irreversible. The dependency of solubility on various factors is due to interactions between the particles, molecule or ions.

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How do you find the frequency of a recorder?

Answers

Answer:

Modern recorders are most commonly pitched at A=440 Hz, but among serious amateurs and professionals, other pitch standards are often found. For the performance of baroque music, A=415 Hz is the de facto standard, while pre-Baroque music is often performed at A=440 Hz or A=466 Hz.

Explanation:

Choose all the answers that apply. According to Newton's second law of motion: objects at rest will remain at rest unless acted upon by an outside force the greater the magnitude of force, the faster the acceleration mass has an inverse relationship with acceleration every action has an equal and opposite reaction acceleration is caused by unbalanced forces​

Answers

Answer: The answers aplicable would be

1) The greater magnitude of force, the faster the acceleration.

2) Acceleration is caused by unbalanced forces.

(b)
Analysis of a molecule of DNA showed that cytosine accounted for 42 per cent of the
content of the nitrogenous bases. Calculate the percentage of bases in the molecule
which would be thymine. Show your working.

Answers

8%

Explanation:

In a DNA molecule the no. of Adenine bases equal to that of Thymine bases

The no. of Cytosine bases equal to that of Guamine bases.

If we take no. of Thymine bases as x and no. of Cytosine bases as y,

Adenine + Thymine + Cytosine + Guamine = 100

x + x + y+y = 100

2( x+y) = 100

x+y = 50

y=42

therefore x= 50-42 = 8%

IS N2 (diatomic molecule of nitrogen considered a chemical compound can it be split into two or more simpler substances?

Answers

2Oh+6ho=45737E Electrolysis

What is called exothermic ​

Answers

An exothermic process is one that gives off heat.

Explanation:

This heat is transferred to the surroundings. An endothermic process is one in which heat has to be supplied to the system from the surroundings.

Describe how the suspects used the chemicals found at the crime scene to make the copper coins look silver.

Answers

The chemicals found at the crime scene although not mentioned must be Sodium zincate.

Discussion:

An interesting demonstration to show plating and alloys is the conversion of copper coins to silver look-alike coins.

A 'copper' coin when dipped into a solution of sodium zincate in contact with zinc. The coin is plated with zinc and appears silver in colour.

This is a common chemistry classroom trick.

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The table below gives the atomic mass and relative abundance values for the three isotopes of element M.

Relative abundance (%) Atomic mass (amu)
78.99 23.9850
10.00 24.9858
11.01 25.9826

What is the average atomic mass (in amu) of element M?
2.86
5.36
24.30
24.98

Answers

Answer:

24.30

Explanation:

Multiply the relative abundance by the atomic mass of each isotope, add the results together, and divide by 100. Then round to the correct amount of significant figures.

(78.99 x 23.9850) + (10.00 x 24.9858) + (11.01 x 25.9826)/100

24.30 is the average atomic mass (in amu) of element M.

What is an atomic mass?

Atomic mass is the quantity of matter contained in an atom of an element.

Multiply the relative abundance by the atomic mass of each isotope, add the results together, and divide by 100. Then round to the correct amount of significant figures.

(78.99 x 23.9850) + (10.00 x 24.9858) + (11.01 x 25.9826)

2430.501576 ÷ 100

24.30

Hence, 24.30 is the average atomic mass (in amu) of element M.

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- A beam of electrons has.....
(A) Wave properties.
(B) Particle properties.
(C) Both of these
(D) Neither of these​

Answers

Answer:

(C) Both of these

Explanation:

A beam of electrons has both of these Wave properties and Particle properties.

Shanika is an engineer at an amusement park who is experimenting with changes to the setup for a magnetic roller coaster ride. In one ride, there are two identical roller coaster cars (orange and green) that start on opposite sides of a large magnet located at the center of a station. Shanika wants to get the largest increase in potential energy she can by moving one car one space to the left or the right. Shanika can move the orange car to point A or point B, or she can move the green car to point C or point D. Which movement should she make? Why will that movement result in the largest increase in potential energy? Describe the magnetic force that will act on the roller coaster car she moves. What should I do for the Green cart?

Answers

The orientation of the poles of the magnet on the cars and the large

magnet are like poles.

The correct responses are;

First question

Move the orange car from A to B Move the green car from D to C

Second question:

The reason is reducing the distance increases the magnetic field strength

Third question:

It pushes the cars away in the opposite direction.

Fourth question:

Place the green car at point C to get the largest potential energy

Reasons:

Potential energy is the energy an object has due to its location.

Energy is a product of force and distance, and therefore, if the force,

experienced by the object increase, the potential energy of the object

increases.

The strength of a magnetic field, B, is given by the formula;

[tex]\displaystyle B = \frac{\mu_0 \cdot I}{2 \cdot \pi \cdot d}[/tex]

Where;

B = The magnetic field strength

I = Current

d = The distance from the source of the magnet

μ₀ = The permeability of free space = 4·π × 10⁻⁷ T m/A

Therefore, the strength of the magnet is higher closer to the source.

First question

In a magnet, like poles push each other back, and given that the poles of the magnet adjacent to each other are like poles, to get the largest increase in she should move the cars towards the large magnet.

Move the orange car from A to B Move the green car from D to C

Second question:

The reason why the movement will result in the largest increase in potential energy is because like polls repel each other and the strength of a magnetic field increases closer to the magnet

Third question:

The magnetic force that will act on the roller coaster car moved towards the large magnet, pushes the car in the opposite direction.

Fourth question:

The green cart should be moved from point D to point C to get the largest potential energy

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Which compound is an acidic oxide?
Aaluminium oxide
carbon dioxide

copper(II) oxide

magnesium oxide

Answers

Answer:

Carbon dioxide

Explanation:

Metal oxides are basic and Non metal.oxides are acidic.

Al, Be, Zn,Sn ,Pb oxides are amphoteric so they show both acidic and basic properties.

From the above answers Al, Cu and Mg are metals so their oxides are acidic while Carbon is a non metal.so CO2 is an acidic oxide

Help will give brainlyness
Use your periodic table, notes on transition metals, and polyatomic ion table to correctly answer the following:
What is the ionic compound formed from calcium and sulfide ions?
Select one:
O a.
Cas
O b. Ca s
O c. CaSO4
O d. CazS2

Answers

Answer:

The high melting point is also consistent with its description as an ionic solid. In the crystal, each S2− ion is surrounded by an octahedron of six Ca2+ ions, and complementarity, each Ca2+ ion surrounded by six S2− ions.

Explanation:

You can use the periodic table to predict whether an atom will form an anion or a cation, and you can often predict the charge of the resulting ion. Atoms of many main-group metals lose enough electrons to leave them with the same number of electrons as an atom of the preceding noble gas. To illustrate, an atom of an alkali metal (group 1) loses one electron and forms a cation with a 1+ charge; an alkaline earth metal (group 2) loses two electrons and forms a cation with a 2+ charge, and so on. For example, a neutral calcium atom, with 20 protons and 20 electrons, readily loses two electrons. This results in a cation with 20 protons, 18 electrons, and a 2+ charge. It has the same number of electrons as atoms of the preceding noble gas, argon, and is symbolized Ca2+. The name of a metal ion is the same as the name of the metal atom from which it forms, so Ca2+ is called a calcium ion.

When atoms of nonmetal elements form ions, they generally gain enough electrons to give them the same number of electrons as an atom of the next noble gas in the periodic table. Atoms of group 17 gain one electron and form anions with a 1− charge; atoms of group 16 gain two electrons and form ions with a 2− charge, and so on. For example, the neutral bromine atom, with 35 protons and 35 electrons, can gain one electron to provide it with 36 electrons. This results in an anion with 35 protons, 36 electrons, and a 1− charge. It has the same number of electrons as atoms of the next noble gas, krypton, and is symbolized Br−. (A discussion of the theory supporting the favored status of noble gas electron numbers reflected in these predictive rules for ion formation is provided in a later chapter of this text.)

Please hurry and help 20 and points and brainelest

Answers

A simple example of convection currents is warm air rising toward the ceiling or attic of a house. Warm air is less dense than cool air, so it rises. Wind is an example of a convection current. Sunlight or reflected light radiates heat, setting up a temperature difference that causes the air to move., AKA the thingy that says the different air thingys

For the reaction, calculate how many moles of the product form when 0.046 mol of O2 completely reacts.
Assume that there is more than enough of the other reactant.
2Ca(s)+O2(g)→2CaO(s)
Express your answer using two significant figures.

Answers

Answer: 0.023 moles of CaO.

Explanation:

The balanced equation tells us that we'll get 2 moles of CaO for every one mole of O2.  Since we have 0.046 moles of O2, we'll get 0.023 moles of CaO.  (2 sig figs)

a
A sample of gas has a volume of 3.50 L and a pressure of
125 mm Hg. What will the new pressure be when the volume
is decreased to 2.75 L? The temperature stays the same.

Answers

Answer:

159.09 mmHg

Explanation:

The new pressure can be found by using the formula for Boyle's law which is

[tex]P_2 = \frac{P_1V_1}{V_2} \\[/tex]

where

P1 is the initial pressure

P2 is the final pressure

V1 is the initial volume

V2 is the final volume

From the question we have

[tex]P_2 = \frac{125\times3.50 }{2.75} = \frac{437.5}{2.75} \\ = 159.090909...[/tex]

We have the final answer as

159.09 mmHg

Hope this helps you

the proton concentrations of three solutions at 25 °c are given. classify the solutions as acidic, basic, or neutral.

Answers

This problem is giving information about the proton concentrations of three solutions at 25 °C. Despite they are not numerically given, we can propose three scenarios to see how to approach the question.

Let the following solutions to come up:

[H⁺] = 2.63x10⁻³ M

[H⁺] = 1.00x10⁻⁷ M

[H⁺] = 4.511x10⁻⁹ M

The first step, will be the calculation of the pH for each solution via:

pH = -log([H⁺])

So that they turn out to be:

pH = -log(2.63x10⁻³ M) = 2.580

pH = -log(1.00x10⁻⁷ M) = 7.000

pH = -log(4.511x10⁻⁹ M) = 8.3457

In such a way, since acidic solutions have a pH below 7, neutral have a pH equal to 7 and basic have it above 7, we infer the first one is acidic, second one is neutral and third one is basic.

Thus, you can reproduce this methodology with the proton concentrations you are given.

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how long does vacuum sealed raw meat last in the freezer?

Answers

Answer:

Frozen Meats – Frozen raw meats that are properly vacuum sealed can be stored in the freezer from 1-3 years depending on the type of meat. However, raw meat that is not vacuum sealed will only last 1-12 months depending on the meat.

Explanation:

hop this helps

Answer: Six months or three years

Explanation: Frozen meats, poultry, and fish can last in the freezer for up to six months and when they are vacuum sealed, frozen meats can stay fresh and free from freezer burn for up to 3 years.

a chemical compound in which ions are held together in a lattice structure by ionic bonds

Answers

Answer:

Ionic compounds contain ions and are held together by the attractive forces among the oppositely charged ions

Explanation:

Common salt (sodium chloride) is one of the best-known ionic compounds. Molecular compounds contain discrete molecules, which are held together by sharing electrons (covalent bonding).

What type of molecule is pentanal?
A. Aldehyde
O B. Ketone
O C. Alcohol
O D. Ester

Answers

Answer:

[tex] \huge \color{indigo} \boxed{a. \: aldehyde}[/tex]

Explanation:

Pentanal is considered to be a fatty aldehyde lipid molecule. These are compounds containing more than one aldehyde group. Pentanal is a very hydrophobic molecule, practically insoluble in water, and relatively neutral.

Draw the structure of the product that is formed when the compound shown below undergoes a reaction with 1 equivalent of ch3mgi and then is treated with water.

Answers

When the compound shown is treated CH3MgI followed by water, 1,3 - cyclohexadienol is formed.

Grignard reagent is an alkylmagnesium halide. Grignard reagents are important synthetic tools in chemistry. They are used to synthesize and number of compounds in the laboratory.

When the Grignard reagent, CH3MgI is reacted with compound shown followed by treatment with water, the product of the reaction is 1,3 - cyclohexadienol whose structure is shown in the second image attached to this answer.

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Which shows the general structure of a carboxylic acid?
O A. R
O-R
R
O R
B. R-O-R
C. R-OH
OD ROH

Answers

The general structure of a carboxylic acid is shown by option D.

In organic chemistry, a carboxylic acid is an organic acid that consists of a carboxyl group connected to an R-group. the overall components of carboxylic acid are R−COOH or R−CO₂H, with R referring to the alkyl, alkenyl, aryl, or other institution. Carboxylic acids arise broadly.

A carboxylic acid is a natural compound that incorporates a carboxyl group (C(=O)OH). the general formulation of a carboxylic acid is R–COOH, with R referring to the relaxation of the molecule. A carboxylic acid may be the concept of a mixture between functional corporations: an alcohol institution, related to hydrogen certain to oxygen, which attaches to a carbonyl institution, involving a carbon double sure to oxygen.

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What is an empirical formula

Answers

Answer:

a formula giving the proportions of the elements present in a compound but not the actual numbers or arrangement of atoms.

Explanation:

Answer:

Meaning of Empirical formula :-

A formula giving the proportions of the elements present in a compound but not the actual numbers or arrangement of atoms.

Defination of Empirical formula :-

The empirical formula of a chemical compound is the simplest whole number ratio of atoms present in a compound. A simple example of this concept is that the empirical formula of sulfur monoxide, or SO, would simply be SO, as is the empirical formula of disulfur dioxide, S₂O₂.

Explanation:

Hope this helps you XD ✌️Carry on learning !!

Explain what is wrong with this electron dot diagram for the element nitrogen

Answers

Hello, is there anyone here a pharmacy technician?

is isopropyl alcohol the same as hydrogen peroxide

Answers

Answer:

Unlike isopropanol, hydrogen peroxide is not a type of alcohol. You might recognize its chemical formula, H2O2, as being similar to that of water (H2O). The difference is that hydrogen peroxide has two oxygen atoms instead of one. That one extra oxygen atom makes it a strong oxidizer.

What is a quick way to determine how many energy levels an element possesses?
A.
Divide the element's atomic number by eight.
B.
Find the element's group number on the periodic table.
C.
Find the element's period number on the periodic table.
D.
Divide the element's atomic mass by eight.

Answers

Answer:

c

Explanation:

just got this question

why the mixture of bromine and ethane is discoloured when left in the sun​

Answers

Answer:

In the presence of UV light, ethane will react with bromine in a substitution reaction. UV light is the condition under which the reaction will occur so it is written above the arrow in the chemical equation. As the reaction proceeds, the intensity of the re-brown colour of the bromine water decreases.

Answer:

here ya go

Explanation:

combining bromine and ethane leads to a brown gas or liquid which is made of the elements. it is a gas at room temperature and does not affect human beings. there are many uses for bromine compounds but they are mainly used for the manufacturing of chlorine, fire retadants, water purification, graphy chemicals and pharmaceutcals. it is a naturally occurring element that can be found in animals such as sharks since they produce their own.

¿Qué relación existe entre la teoría del octeto de Lewis con los enlaces iónicos y
covalentes?

Answers

Por definición de enlace iónico, covalente y regla del octeto, la relación existente entre la teoría del octeto de Lewis con los enlaces iónicos y  covalentes es que dichos enlaces se producen con el objetivo de completar la última capa de electrones y adquirir estabilidad.

Enlace iónico

Por un lado, se produce un enlace iónico entre átomos metálicos y no metálicos, donde los electrones se transfieren completamente de un átomo a otro. Durante este proceso, un átomo pierde electrones y otro los gana, formando iones. Por lo general, el metal cede sus electrones formando un catión al elemento no metálico, que forma un anión.

Enlace covalente

Por otro lado, el enlace covalente es el enlace químico entre átomos donde los electrones se comparten, formando una molécula. Se establecen enlaces covalentes entre elementos no metálicos. El par de electrones compartidos es común a los dos átomos y los mantiene unidos.

Regla del octeto

En ambos casos se cumple con la regla del octeto, que establece que los átomos de los elementos se enlazan unos a otros en el intento de completar su capa de valencia con ocho electrones. Es decir que los átomos van a tender a ceder o compartir electrones para completar ocho electrones en la capa de valencia mediante un enlace iónico, covalente o metálico.

En otras palabras, el objetivo es tener la configuración electrónica del gas noble más cercano, teniendo así la última capa de electrones completa y adquiriendo estabilidad.

En resumen

En resumen, la relación existente entre la teoría del octeto de Lewis con los enlaces iónicos y  covalentes es que dichos enlaces se producen con el objetivo de completar la última capa de electrones y adquirir estabilidad.

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