Answer:
d.
Explanation:
It is a force that occurs when surfaces touch each other.
Answer:
The pH is 9,21.
Explanation:
The pH indicates the acidity or basicity of a substance. PH values between 0 and less than 7 indicate acidic solutions, 7 neutral and higher than 7 to 14 basic. It is calculated as
pH = -log (H 30+)
pH= -log (6,2 x 10^-10)
<em>pH=9,21</em>
Halogens are a group of elements consisting of Fluorine, Chlorine, Bromine, Iodine and Astatine. In their ionic form, they have a superscript of -1, for example, chloride ion is Cl-1. These means that they readily accept one electron in order to achieve the Octet rule. The Octet rule states that each atom must contain 8 electrons in their valence shell for it to be stable. The most stable set of elements are the noble gases. Because they already fulfill the Octet rule, they no longer take part in reactions. Halogens are also very electronegative, meaning, they attract more electrons toward them. This is also a consequence of the Octet rule.
From the choices, the answers would be:
<span>they require only one electron to complete their outer shell
they have a high electronegativity</span>
Answer:
The 2292 moles of CO are needed to react completely with 122 Kg of Fe₂O₃.
Explanation:
Given data:
Mass of Fe₂O₃ = 122 Kg ( 122×1000 = 122000 g)
Moles of CO = ?
Solution:
Chemical equation:
Fe₂O₃ + 3CO → 2Fe + 3CO₂
Number of moles of Fe₂O₃:
Number of moles = mass/ molar mass
Number of moles = 122000 g /159.69 g/mol
Number of moles = 764 mol
Now we will compare the moles of Fe₂O₃ with CO.
Fe₂O₃ : CO
1 : 3
764 : 3×764 =2292 mol
The 2292 moles of CO are needed to react completely with 122 Kg of Fe₂O₃.
Answer:
PROTON AND NEUTRON
Explanation:
- The mass of proton is :
A proton is one of the main particles that make up the atom . The other two particles are neutron and electron. Protons are found in the nucleus of the atom.This is a tiny , dense region at the centre of the atom. Protons have a positive charge of one (+1) and a mass of 1 atomic mass unit ( amu ) , which is about . Together with neutrons , they make up virtually all of the mass of an atom.
- The mass of neutron is also approximately: but a little more than that .
Atoms of all elements - except Hydrogen , have neutrons in their nucleus . Unlike protons and electrons , these have no charge - they are electrically neutral . The mass of a neutron is slightly greater than the mass of a proton but not very significant
