4.) an element cannot be decomposed by a chemical change, it is a pure substance and no other materials compose it.
Answer:
inerpreting an author's words and using imagination to picture events
Explanation:
please mark this answer as brainlest
Answer:
Brainliest pls
Explanation:
1 mole of a substance contains Avagadro’s number of particles,
i.e. 6.023*10^23
By unitary method,
5 moles of oxygen contains 5 times the Avagadro’s number of particles
i.e. 5* (6.023*10^23) = 3.0115*10^24 number of particles.
Now, the further answer depends on what particles the question concentrates on.
If number of atoms are asked , the above answer must be multiplied by 2, because oxygen is a diatomic gas and each atom contributes to be a particle.
therefore, 5 moles of oxygen has 6.023*10^24 atoms.
If number of molecules asked, the above answer is directly written...
Answer:
Be (899 kj/mol) , Se (940.9 kj/mol), Ne(2081 kj/mol), He (2370 kj/mol),
Explanation:
For noble gases as they have complete octet so they require high amount of energy to remove the electron.
Trend along period:
As we move from left to right across the periodic table the number of valance electrons in an atom increase. The atomic size tend to decrease in same period of periodic table because the electrons are added with in the same shell. When the electron are added, at the same time protons are also added in the nucleus. The positive charge is going to increase and this charge is greater in effect than the charge of electrons. This effect lead to the greater nuclear attraction. The electrons are pull towards the nucleus and valance shell get closer to the nucleus. As a result of this greater nuclear attraction atomic radius decreases and ionization energy increases because it is very difficult to remove the electron from atom and more energy is required.
Trend along group:
As we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased.
As the size of atom increases the ionization energy from top to bottom also decreases because it becomes easier to remove the electron because of less nuclear attraction and as more electrons are added the outer electrons becomes more shielded and away from nucleus.
Answer:
11.3 g.
Explanation:
Hello there!
In this case, since the combustion of butane is:

Thus, since there is a 1:5 mole ratio between butane and water, we obtain the following mass of water:

Therefore, the resulting mass of water is:

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