Answer:
oxygen
Explanation:
because the 2nd shell is not complete which is suppose to be 8 and since oxygen is 8 it first shell is 2 which is complete and the second shell which is 6 is not complete because we all know that 2+6=8 but the standard shell is
K-2
L-8
M-8
Answer: 68
Explanation:
Isotopes of an element have same number of protons but different number of neutrons. Which means isotopes of an element have same atomic number but different mass number.
Atomic number is equal to the number of protons or the number of electrons for a neutral atom and is specific to a particular element.
Mass number is the sum of number of protons and the number of neutrons.
Given : atomic number of element Q = 68 = number of protons
Mass number of isotope Q-136 = 136
But as isotopes have same atomic number, the number of protons will be same and hence there are 68 protons are in a neutral atom of this isotope.
Answer:
A and C
Explanation:
The term formula unit is use to indicate Simple-Whole Ratios of ions in a compound. KEY WORD! RATIO!
Answer:
167.980.
Explanation:
Hello!
In this case, since additions involving the display of the result with the appropriate number of significant figures involve the solution of the system without looking at them:

Considering that 156.325 is significant to the thousandths and 11.65498 to the hundred thousandths, we infer that the result should be taken to the thousandths as well as 156.325; thus, we obtain:

Because the second decimal nine is rounded to ten and therefore the 7 is taken to 8.
Best regards!
Answer:
The correct option is C.
Solutions with low pH values have sour taste.
Explanation:
Low pH value show acidic property which can be define as , -log of conc. of hydrogen ion.
Acid has following properties
- Sour taste
- Turn blue litmus into red
- corrosive
-OH group: Base have OH groups. So it is not correct option so it not correct for low pH i.e. acid
turns litmus paper blue: Base turn red litmus into blue, so it not correct for low pH i.e. acid
feels slippery: Bases are mostly slippery like soap
tastes sour: Sour taste is for acid and bitter taste is for base. So it is correct option for acid