The answer is c. because you have to increase concentration of h2
The number of valence electrons of an element can be determined by the periodic table group (vertical column) in which the element is categorized
During the dark ages-All that wasn't around the christian religion were lost. Knowledge and discoveries before the Dark Ages were mainly in Greek ideas. Biblic scripts however were in Latin. Therefore all inventions up to the dark ages were lost and only religious scripts preserved in the churches. Outside the church, no one knew how to write, read or even communicate.
Answer:
At the melting point, some molecules overcome the forces of attraction. Energy gained after the the solid melts increases the average kinetic energy or the temperature. When liquid is freezing the energy flows out the the liquid. As the kinetic energy decreases, they move more slowly.
Explanation:
Answer:
The element is strontium and the number of neutrons it have is 51.
Explanation:
Based on the given information, the ionic compound is,
XCl₂ ⇔ X₂⁺ + 2Cl⁻
X2+ is the ion of the mentioned element
As mentioned in the given question, the number of electrons of the element X is 36 and as seen from the reaction the charge present on the ion is +2. Now the atomic number will be,
No. of electrons = atomic number - charge
36 = atomic number - 2
Atomic number = 38
Based on the periodic table, the atomic number 38 is for strontium element, and the sign of strontium is Sr. Hence, the element X is Sr.
Now based on the given information, the mass number of the element is 89. Now the no. of neutrons will be,
No. of neutrons = mass number - atomic number
= 89 - 38
= 51 neutrons.
