Answer:
Explanation:
The correct measurement is .710 s which is equal to .71 s so second measurement that is 0.71 s is most accurate measurement .
B. 0.71s is the most accurate .
Precision depends upon measuring instrument . Measurement by highly precise instrument has greater precision .
The measurement of 0.75 ± 0.002s must have been taken from high precise instrument because it is capable of making measurement upto 3 decimal points .
Hence
C 0.75 ± 0.002s is most precise measurement .
Answer:
three valence electrons
Explanation:
Gallium has three electrons in the outer energy level and therefore has three valence electrons. The identification of valence electrons is vital because the chemical behavior of an element is determined primarily by the arrangement of the electrons in the valence shell.
Answer:
3 Ca(OH)2 + 2 K3PO4 ---> Ca3(PO4)2 + 6 KOH
Explanation:
Just balance each atom on both sides.
Iodine is one of seven elements that usually form as diatomic molecules. These other "diatomics" are

and

. They typically bond to themselves.
Iodine has seven valence electrons. Using valence shell electron pair repulsion (VSEPR) theory, we can predict the Lewis dot structure for

. We see there are fourteen electrons, and we can make a covalent bond, leaving three lone pairs on each atom. The bond replaces two electrons, so the number of electrons shared is two.