please someone answer and help :) ​

Answer:

yes the cell membranes are semi permeable

Answer:

C

Explanation:

A year is a complete revolution around the Earth

Answer:

What the heck is "K" but I beleive 75 is the answer, but maybe wait for sumone else to answer.

Explanation:

Answer:

30 C

Explanation:

Answer

Au2s

please mark me as brainlist

Answer: is C&A

Explanation:the electric motor converts  electricity in to mechanical energy

the  electric generator converts mechanical energy to electricity so it could not be D.

and they don't use batteries as their main source of power so it could not be B.

hence forth it is C&A

HOPE THIS HELPS!!!!!!1

PLEASE MARK BRAINLIEST!!

Answer:

Azucar, bicarbonato de sodio, lavandina, vinagre, amoniaco.

Explanation:

Podemos numerar estos compuestos

Azucar → Sacarosa → C₁₂H₂₂O₁₁

Lavandina → Hipoclorito de sodio → NaClO

Vinagre → Ácido acético → CH₃COOH

Bicarbonato de sodio → NaHCO₃

Amoníaco → NH₃

Answer:

D. Ionic

Explanation:

It has ionic bonding! Good luck ^^

Answer:

D. All of the above

Explanation:

Molecules, ions, and pure elements might be included in a chemical reaction. Therefore, option (d) is correct.

A chemical reaction can be described as a reaction that brings the chemical conversion of one chemical substance to another chemical substance. The reactions cause chemical changes that include the rearrangement of electrons in order to create and break bonds between atoms.

The compound or molecules which are primarily utilized in a reaction are called reactants. Chemical reactions give products, which possess characteristics different from the reactants of the reaction.

Chemical reactions take place at a definite rate of reaction at a given concentration, temperature, and pressure. The rate of reaction increases with the rising temperature of the reaction as more activation energy is available for reactant molcules collisions.

Therefore, in a chemical reaction reactants and products can be present as Molecules, ions, and pure elements.

Learn more about Chemical reactions, here:

brainly.com/question/22817140

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Answer:

B. +5

Explanation:

Answer:

The nucleus of the atom contains two subatomic particles, the protons which are positively (+) charged and the neutrons which are neutral (no charge).

Explanation:

Answer:

The nucleus is a collection of particles called protons, which are positively charged, and neutrons, which are electrically neutral.

Explanation:

Answer:

the person above me is right

hope you do good on your test

Explanation:

Answer:

Explanation:  15

Answer:

N, P, As, Sb

Explanation:

Elements present in the same group having same number of valence electrons. The first option is correct from given options because nitrogen, phosphorus, arsenic and antimony are present in same group thus having same number of electrons in outer most  energy level.

Electronic configuration of N:

N₇: [He] 2s² 2p³

Electronic configuration of P:

P₁₅: [Ne] 3s² 3p³

Electronic configuration As:

As₃₃: [Ar] 3d¹⁰ 4s² 4p³

Electronic configuration Sb:

Sb₅₁: [Kr] 4d¹⁰ 5s² 5p³

Here it is clear from electronic configuration all these elements have five number of valence electrons.

Answer:

The atomic mass is 101.

Explanation:

Protons and neutrons are the only particles that contribute to mass. Electrons do have a mass, but it's so miniscule and insignificant that it doesn't contribute to the mass of an atom. In every instance of calculating atomic mass, add the number of protons to the number of neutrons.

Therefore,

44 + 57 = 101

number of protons + number of neutrons = atomic mass

Also, there can never be a negative amount of protons or neutrons, so if you get a negative number, there's something wrong.

Bonus Information:

Don't confuse mass with charge! As it says in its name, neutrons are neutral or have no charge. Protons (+) and electrons (-) are the only particles that have a charge, so calculating that would be different.

If you were calculating the atomic charge with the same numbers, your answer would be:

44 - 42 = 2

Charge = +2

What To Remember:

M = p + n

C = p - e

C = atomic charge, M = atomic mass, p =protons, n = neutrons, e = electrons

I hope this helps!

Answer:

C ! :)

Explanation:

Answer:

The correct answer is A

Explanation:

LOW-DENSITY PARRTICLE

The volume of H₂ evolved at NTP=0.336 L

Reaction

Decomposition of NH₃

2NH₃ ⇒ N₂ + 3H₂

conservation mass : mass reactants=mass product

0.28 NH₃= 0.25 N₂ + 0.03 H₂

2 g H₂ = 22.4 L

so for 0.03 g :

[tex]\tt \dfrac{0.03}{2}\times 22.4=0.336[/tex]

Answer:

It is b

Explanation:

Explanation:

Load=500N

Effort=100N

Now,

We have,

Mechanical advantage= Load / effort

= 500/100

=5

Therefore, mechanical advantage is 5.

Taking into account the Gay-Lussac's Law, the pressure will increase by a factor less than three.

Gay-Lussac's law indicates that, as long as the volume of the container containing the gas is constant, as the temperature increases, the gas molecules move faster. Then the number of collisions against the walls increases, that is, the pressure increases. That is, the pressure of the gas is directly proportional to its temperature.

In summary, when there is a constant volume, as the temperature increases, the pressure of the gas increases. And when the temperature is decreased, the pressure of the gas decreases.

Mathematically, Gay-Lussac's law indicates that the ratio of pressure to temperature is constant:

[tex]\frac{P}{T} =k[/tex]

Studying two different states, an initial state 1 and a final state 2, it is satisfied:

[tex]\frac{P1}{T1} =\frac{P2}{T2}[/tex]

In this case, a given mass of gas in a rigid container is heated from 100 ° C to 300 ° C, that is, it is heated from 373 ° K to 573 ° K. This indicates that the temperature is increasing by a factor less than three. Since pressure is directly proportional to temperature, pressure must increase in the same proportion.

Finally, the pressure will increase by a factor less than three.

Learn more:

Answer:

7m/s

Explanation:

Is the acceleration of the helicopter

Answer:

I searched the answer up on Brainly so its not my credit.

Explanation:

The answers D.

"If you have learned that metal + nonmetal ⟶ ionic bond, the answer is D, because N and C are the only pair of nonmetals.

However, if you have learned that a bond is ionic if the electronegativity difference (ΔEN) between the two atoms is greater than 0.7, the answer is A, B, and D.

The Li-Cl bond is definitely ionic.

For Na and C, ΔEN =1.62, so the Na-C bond is a highly polar covalent bond.

For Mg and C, ΔEN = 1.24, so the Mg-C bond is a polar covalent."

Hope this helps :D

Answer:

c

Explanation:

its c

Earth contains a spinning electric filed. The spinning of earth core creates its magnetic field. Thus, option D is correct.

A body which rotates in its own axis is called a spinning body. Earth rotates about its along with revolving around sun.  The outer core of earth generates electric current. This is called telluric current.

Flow of this current creates an electric current which is parallels to the surface of earth. The direction of magnetic field lines will be perpendicular to the direction of current. But it comes stronger when parallel to current.

A rotating electric current results in the generation of a magnetic field. Thus spinning of  earth core generates a magnetic field and therefore, option D is correct.

To learn more about magnetic field, refer the link below:

https://brainly.com/question/11514007

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Answer:

Earths rotation

Explanation:

Answer:

because if there was not four diferent season we would not have a day or a night because we would not be moving

Explanation:

Answer:

The reaction for which ΔH is positive are endothermic reactions. Explanation: The energy changes occur during the bonds formation and bonds breaking

Answer:

NaOH(aq)

Explanation:

NaOH(aq) is known to precipitate Mn^2+ ions according to the following reaction; Mn^2+(aq)+2OH^−(aq)↽−−⇀Mn(OH)2(s)

Hence, manganese(II) oxide reacts more readily with NaOH(aq) under ordinary conditions precipitating the metal hydroxide solid. This is one of the characteristic reactions of Mn^2+.

Answer: C

Explanation:

The average atomic mass of a sample closer to the mass of Li-6

Isotopes are atoms whose no-atom has the same number of protons while still having a different number of neutrons.  

So Isotopes are elements that have the same Atomic Number (Proton)  

Atomic mass is the average atomic mass of all its isotopes  

In determining the mass of an atom, as a standard is the mass of 1 carbon-12 atom whose mass is 12 amu  

Mass atom X = mass isotope 1 . % + mass isotope 2.%  

three Li-6, mass number = 6

two Li-7, mass number = 7

total abundance = 5

abundance for Li-6 =

[tex]\tt \dfrac{3}{5}\times 100\5=60\%[/tex]

abundance for Li-7 =

[tex]\tt \dfrac{2}{5}\times 100\5=40\%[/tex]

Average atomic mass :

[tex]\tt (0.6\times 6)+(0.4\times 7)=6.4[/tex]

Answer:

there are eight electrons