Which of the following observations indicates that atoms of all elements contain small, negatively charged particles? Alpha particles are repelled by cathode rays of elements. Cathode rays are deflected towards a positively charged rod. A particular frequency of light is produced by a gas in an excited state. Certain areas of the atom called orbitals contain all the charged particles.

12

Explanation:

Look at the number directly after the number you want to keep. I'm your case you want to keep the first two numbers and the number directly after is 4 so there is no need to round up. Keep your 12 without a decimal.

Bohr describe the arrangement of particles within an atom by: O D. Protons and neutrons form the nucleus of the atom, with electrons orbiting it.

This hypothesis states that the atom's core is a small, compact, positively charged nucleus. Protons which have a positive charge and neutrons which are neutral are both found in the nucleus.

Specific energy levels or electron shells are where the negatively charged electrons orbit the nucleus. Due to the quantization of these energy levels, only a limited number of discrete energy states are accessible to electrons.

Therefore the correct option is D.

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Answer:

Ethene.

Explanation:

To know the name of the compound given above, we must:

1. Determine the number of carbon present in the compound.

2. Determine whether a single, double or triple is present in the compound.

3. Combine the above to get the name.

Now, let us name compound given above. This is illustrated below:

1. The compound contains two (2) carbon atom.

2. The compound contains a double bond. Therefore, the compound is an alkene.

3. An alkene with two carbon atoms is called ethene.

Therefore, the name of the compound given in the question is called ethene.

Answer:

other guy is right :)

Explanation:

if you look up "ethene hydrocarbon" online, the image attached in the question pops up!

Answer:

Spraying perfume in one corner of the room and the smell travels to the other side of the room

Explanation:

Answer:

I think if u will clear your topic it would be more helpful.

But if u r unable to do it, then u can just memorise it.

See, i will try to help u.

Salts are formed when acids react with bases.

and this reaction is called neutralisation reaction.

e.g. HCl+NaOH=NaCl+H2O.

It is very easy.

Other examples:

H2SO4+Mg(OH)2=MgSO4+2H2O.

There may be some other reactant with acid like u have mentioned above.

hope it helps u....

plz mark as brainliest...

Answer:

One factor that affects that affects the direction of the current is the direction of motion of the wire

Explanation:

According to Fleming's right hand rule when a conductive wire which is within a circuit is moved through a magnetic field, due to Faraday's law of electromagnetic induction an electric current is induced in the wire such that the direction of motion of the wire, the direction of the magnetic field and the direction of the electric current are perpendicular to each other such that if the right hand has the thumb middle finger and the index finger held perpendicular to each other

The motion of the wire being in the direction of the wire

The first or index finger points in the direction of the magnetic field

The middle finger points in the direction of the induced electric current

Therefore, the direction of the the current depends on the direction of motion of the wire.

Answer:

Explanation:

percent yield is ratio of actual yield or experimental yield divided by theoretical yield multiplied by 100 .

percent yield of 93.4 % means , the actual yield is 93.4 % what was expected from the reaction on the basis of given chemical reaction .

If in the experimental process , some sodium hydrogen carbonate is left unreacted due to absence of reactant HCl which is also required to obtain product , the percent yield will be increased if the required HCl is also provided .

Hence the percent yield will be increased if required HCl is made available .

Answer:

it would decrease [h+]

Explanation:

 This is due to  neutralization If a base is added to an acidic solution, the solution becomes less acidic and its position changes to the middle of the pH scale.

hope this helps

Answer:

Raise the pH

decrease [H+]

Explanation:

=> Adding base would raise the pH (Bases have more pH and Acids have less pH)

=> Adding base would decrease the concentration of [H+] ions as it contains hydroxyl ions which neutralized with H+ ions so as a result the concentration of [H+] ions decreases.

Answer:

Blue wave.

Explanation:

Answer:

Protons and neutrons have almost the same mass and are both located in the nucleus of the atom

Answer:

Protons and neutrons have almost the same mass and are both located in the nucleus of the atom. Protons are charged particles. Neutrons are neutral particles. ... The positive charge of the protons in the nucleus is balanced by the negative charge of the electrons.

Answer:

B. reflection

Explanation:

Rigid transformations are methods involved in changing the dimensions or orientation of a given figure. The methods are; dilation, rotation, translation and reflection.

Reflection is the process in which a given figure is turned or flipped with respect to a point or line of reference.

In the given question,

ΔDEF ≅ ΔD'EF' (Side-Side-Side congruence property)

This implies that ΔDEF was reflected about point E to produce ΔD'EF'. Thus the required rigid transformation is reflection.

Answer:

Is C - Rotation

Explanation:

I have right on my test

Answer:

[tex]\boxed{2}[/tex]

Explanation:

Alkaline earth metals are in group 2. The number of valence electrons of elements in group 2 is 2.

2 valence electrons do the alkaline earth metals have. Therefore, option B is correct.

Alkaline earth metals are the elements in Group 2 of the periodic table, which includes beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).

In general, elements in Group 2 have two valence electrons. Valence electrons are the electrons located in the outermost energy level (or shell) of an atom. For the alkaline earth metals, the outermost energy level is the second energy level, which can hold up to 8 electrons.

Only the two electrons in the s sublevel of the second energy level are considered valence electrons. These two valence electrons are involved in chemical reactions and bonding.

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Answer:

32. Opcion E

Explanation:

ZO₂ podemos entenderlo como dióxido de Z

1 mol de ZO₂ contiene 1 mol de Z y 2 moles de O₂ por lo que si la masa molar es de 64 g/mol, podemos plantear lo siguiente

Masa de Z + 2 masa de O = 64 g/mol

Sabemos que la masa del oxígeno es 16 g/mol

x + 2. 16 g/mol = 64 g/mol

x = 64 - 32 →  32 g/mol

La masa atómica coincide con la masa molar, por lo tanto la masa atomica de Z es 32.

Considerando la definición de masa molar, la respuesta correcta es la opción E: La masa atómica de Z debe ser 32.

La masa molar es la masa de un mol de una sustancia, la cual puede ser un elemento o un compuesto, esto es, es la relación entre la cantidad de sustancia y su masa.

En otras palabras, la masa molar es la cantidad de masa que una sustancia contiene en un mol.

En la tabla periódica, se puede encontrar la masa molar de los elementos, también llamada masa atómica o peso atómico.  

Para calcular la masa molar de un compuesto, también llamado masa o peso molecular, se debe sumar la masa molar de los elementos del compuesto multiplicado por su cantidad en el compuesto.

Entonces, en este caso, siendo la masa molar del oxígeno (O) 16, y la masa molar del compuesto ZO₂ 64, y denominando x a la masa molar de Z, entonces la masa molar del compuesto puede expresarse como:

x + 2×16= 64

Resolviendo:

x + 32= 64

x=64 -32

x=32

Finalmente, la respuesta correcta es la opción E: La masa atómica de Z debe ser 32.

Aprenda más:

Answer:

Explanation:

Nitrate of most of the elements are water soluble . Aluminium nitrate is also one of them . Aluminium nitrate is easily dissolved in water . It forms hydrated salt whose formula is as follows

Al( NO₃ )₃ . 9H₂O

It is a white crystalline salt . It is also soluble in alcohol.

Answer:

A composite material is a material made from two or more constituent materials with significantly different physical or chemical properties that, when combined, produce a material with characteristics different from the individual components.

Explanation:

you're welcome

Answer:

Kindly check Explanation

Explanation:

Given the chemical equation:

2 Mg(s) + O2(g) → 2 MgO(s)

2 molecules of Magnesium + Oxygen gas (Reactant)

→ ( yield)

2 molecules of magnesium oxide (product)

2 in Mg and MgO (coefficients)

2 in Oxygen gas (subscript)

Solid (s) - physical state of Reactant Mg

Gas (g) - physical state of Reactant O2

Solid (s) - physical state of product 2MgO

Answer:

A. increased competition for resources

Explanation:

Answer:

The most important first realization is to find out if the patients are deceased and their bodies are acting under an outside volition such as a virus reanimating the body through the use of the brain stem. If they are still living then they are what would be called infected if dead they are the undead naturally enough. Keep them contained as best you can but knowing scientists they will get free. When facing an infected they can die to any injuries that a normal human can they just won't react to pain so don't shoot for the head blast that thing in the chest then hit it in the head while it's down. Forget hand to hand combat or most close-ranged weapons unless absolutely necessary because close contact means exposure to fluids from the zombie they don't have to bite you to turn you. There is so much more to be said about this I recommend picking up the ZAS zombie survival book I recently got it and have not yet finished it but have learned a great deal.  

Explanation:

Yes I fully understand this is not real and I simply felt like answering in a detailed manner for fun and that book is a serious recommendation.

Answer:

The most significant first acknowledgment is to see whether the patients are expired and their bodies are acting under an outside volition, for example, an infection vivifying the body using the cerebrum stem. On the off chance that they are as yet living, at that point they are what might be called tainted if dead they are the undead normally enough. Keep them contained as well as can be expected however knowing researchers they will get free. When confronting a tainted they can bite the dust to any wounds that an ordinary human can they just won't respond to torment so don't go for the head shoot that thing in the chest at that point hit it in the head while it's down. Disregard hand to hand battle or most close-extended weapons except if completely fundamental since close contact implies introduction to liquids from the zombie they don't need to nibble you to turn you. There is quite a lot more to be said about this I suggest getting the ZAS zombie endurance book I as of late got it and have not yet completed it yet have taken in a lot.

Explanation:

Carbon 14 would be your answer, however if it's more than one answer it would also be Carbon 12, so yeah. Your best bet would be Carbon 14.

Answer:

neutrons :

Explanation:

Protons are positively charged, while electrons are negatively charged. Neutrons are electrically neutral, as the name suggests. The electric charge, noted Q , is a physical quantity.

Answer:

beryllium, magnesium, calcium, strontium, barium, radium

Explanation:

glad to help

Answer:

Ankara is the capital of Turkey! Hope this helped you out! :)

Explanation:

The capital of Turkey is Ankara

hopefully this helped :3

Answer:

These are Kepler's Laws of Planetary Motion

Explanation:

Answer:

its Keplers third law,

then first law,

then second law

Explanation:

Answer:

727.7 torr

Explanation:

Since the gas was collected over water, it is likely to be saturated with water vapour and the total pressure is given as;

Ptotal = Pgas + Pwater

From the question;

Ptotal = 751 torr

Pgas = ?

Pwater = 23.8 torr

Making Pgas subject of equation, we have;

Pgas = Ptotal - Pwater

Pgas = 751 torr - 23.8 torr

Pgas = 727.7 torr

Answer:

2Al2O3 (l) ---> 4Al (l) + 3O2 (g)

Explanation:

The reaction is the electrolysis of aluminium oxide. It decomposes aluminium oxide (Al2O3) into aluminium metal (Al) and Oxygen (O2). In this process, aluminium oxide is molten (liquid state) so that ions can move to complete the electricity circuit.

Al2O3 (l) ---> Al (l) + O2 (g)

Balance the equation:

2Al2O3 (l) ---> 4Al (l) + 3O2 (g)

Answer:

Ionization energy decreases from top to bottom in groups as the size of the atom becomes larger. For example, the first ionization energy of hydrogen is 1310 kJ mol⁻¹. The first ionization energy of lithium is 519 kJ mol⁻¹. Because lithium is a bigger atom and has more protons than hydrogen, its ionization energy is lower. So, in groups, the lower the ionization energy, the larger the atom and the more protons/electrons it has.

Ionization energy also increases from left to right across a period. The more protons in the nucleus, the greater the attraction between the nucleus and the electrons, which makes it more difficult to remove electrons. Helium has an ionization energy of 2370 kJ mol⁻¹ while hydrogen has an ionization energy of 1310 kJ mol⁻¹ because helium's nucleus has 2 protons attracting electrons instead of 1 like hydrogen. So for periods, the higher the ionization energy, the smaller the atom and the more protons/electrons it has.

Ionization energy is the energy required to remove an electron from its orbital around an atom. It increases across a period because the number of protons in the nucleus increases. This creates a stronger attraction between the nucleus and electrons, causing the electrons to be held tighter by the higher nuclear charge. Because the electrons are more difficult to remove, more energy is required which causes the ionization energy to be higher. So for periods, the more electrons the atom has, the higher the ionization energy. Ionization energy decreases down a group because the first electron removed is farther from the nucleus as the number of protons increases. Being farther away from the nucleus makes it easier for the electron to be pulled off as it is more loosely bounded, so less energy is required to remove the electron which causes the ionization energy to be lower. So for groups, the more electrons the atom has, the lower the ionization energy.

Groups are vertical columns going down on the periodic table. If you look at a periodic table, across the top, you will see the numbers 1-18. Those numbers signify the 18 groups of the periodic table. Iodine is a halogen so it is under Group 17 to the far right of the periodic table.

I attached two periodic tables for reference to everything that I've said as I've written a lot. Hope that helps.

Answer:

81.6%

Explanation:

mass of acetylferrocene and ferrocene mixture = 22.092 g

mass ratio acetylferrocene and ferrocene mixture = 1 : 1

The sum of the ratios = 2, therefore the mass of each compound will be half the mass of the mixture

mass of each compound in the sample mixture = 1/2 * 22.09 2= 11.046 g

mass of recovered acetylferrocene = 9.017 g

percentage recovery = mass recovered/mass in sample * 100%

percentage recovery of acetylferrocene = (9.017 g / 11.046 g) * 100%

percentage recovery of acetylferrocene = 81.6%

The nuclei of atoms become unstable when the repelling forces of the protons cannot be balanced by the number of neutrons in the nucleus. It then re-arranges itself randomly to a more stable configuration by emitting any of a series of particles. During radioactive decay, an atom does not collapse.

Since an atom is mostly empty space - that is it’s nucleus is relatively distant from the electron shells so, in the presence of extreme forces such as gravity inthe collapse of a large star, the inward pressures on the atom overcome the natural balance of the atomic structure and the ‘empty space’ disappears as nuclei are mashed together by the intense pressures and a neutron star is formed. Under even more external pressure, even the neutron star can collapse to form a black hole.

The two terms apply to oceanic crust rather than continental crust C. Denser and D. Younger in age

Oceanic Crust Oceanic crust, extending 5-10 kilometers (3-6 kilometers) beneath the ocean floor, is mostly composed of different types of basalts. Geologists often refer to the rocks of the oceanic crust as “sima.” Sima stands for silicate and magnesium, the most abundant minerals in oceanic crust.

Oceanic crust is thin (6 km thick) and dense (about 3.3 g/cm), consisting of basalt, gabbro, and peridotite. They include oceanic sediments (e.g. radiolarites, turbidites) and oceanic crust (e.g. basalt, pillow lava).

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