Faster than the hurricane at least 250 feet
Answer: Melatonin has been used safely for up to 2 years in some people. However, it can cause some side effects including headache, short-term feelings of depression, daytime sleepiness, dizziness, stomach cramps, and irritability. Do not drive or use machinery for four to five hours after taking melatonin.
Answer:
Period and groups are different because
PERIODS are the number of shells
I.e in lame man words the no of circles when drawn an element
GROUPS : these are the number of electrons in the outermost shell
Groups determine the valency*
Ans: 15.1 grams
Given reaction:
Na2CO3 + Ca(OH)2 → 2NaOH + CaCO3
Mass of Na2CO3 = 20.0 g
Molar mass of Na2CO3 = 105.985 g/mol
# moles of Na2CO3 = 20/105.985 = 0.1887 moles
Based on the reaction stoichiometry: 1 mole of Na2CO3 produces 2 moles of NaOH
# moles of NaOH produced = 0.1887*2 = 0.3774 moles
Molar mass of NaOH = 22.989 + 15.999 + 1.008 = 39.996 g/mol
Mass of NaOH produced = 0.3774*39.996 = 15.09 grams
Correct Answer: option C:The pair which consist of molecules having the same geometry is CH2CCI2 and CH2CH2.
Reason:
Both of the above molecules contain double bonds. They are characterized by sp^2 hybridization. Also, they possess a trigonal planar geometry. In trigonal planar system, the molecule consist of three equally spaced sp^2 hybrid orbitals, which arranged at angle 120 degree.
