Answer:
Two elements in same group having similar properties.
Explanation:
The elements shows similar properties if they have same number of valance electrons.
As we move left to right in periodic table the number of valance electrons increases in case of every element
When we move top to down in the group of periodic table the number of valance electrons remain same. So the elements in same group shows similar properties.
For example:
Fluorine and chlorine are present in same group, both have same valance electrons so they shows similar properties.
Electronic configuration of fluorine.
F₉ = [He] 2s² 2p⁵
Electronic configuration of chlorine.
Cl₁₇ = [Ne] 3s² 3p⁵
Both have same number of valance electrons that's why showing similar physical and chemical properties.
Answer:
the load is between the fulcrum and the handle
Explanation:
Answer:
C₄H₈
Explanation:
In the first, you should know the ideal gas law. One of the formula for this concept is:
MW = (δ*R*T) / P where:
MW is molecular weight, δ is density 2,50 g/L, R is the gas constant (0,082 (atm*L) / (mol*K) ), T is temperature (273,15 K at STP) and P is pressure (1 atm).
So:
MW = [2,50 g/L * 0,082 (atm*L) / (mol*K) * 273,15 K ] / 1 atm
MW = 56 g/mol
Then the problem says than butene is composed by 85,7% (of carbon) and 14,3 % (of hydrogen). So:
Carbon mass: 56 g/mol * 85,7% = 48 g/mol / 12 g/mol ( atomic mass of carbon = 4 carbon atoms.
And, hydrogen mass: 56 g/mol * 14,3% = 8 g/mol / 1 g/mol ( atomic mass of hydrogen = 8 hydrogen atoms.
Thus, the molecular mass of butene is: C₄H₈
I hope it helps!