First he is not locking properly up
Answer:
The bronsted- Lowry acid is H₂PO₄⁻
Explanation:
Bronsted-Lowry acid donates a proton (H⁺)
H₂PO₄⁻ + OH⁻ → HPO₄²⁻ + H₂O
In the reaction above, H₂PO₄⁻ is donating the proton to OH⁻ resulting in H₂O and the deprotonated species. This makes it a bronsted-Lowry acid.
Option B: 4.3
There are following rules for rounding off numbers:
1. If the rounding digit has digit less than 5 (1,2,3 and 4) to its right, all the digits on right side of the rounding digit will drop out.
2. If the rounding digit has digit equal and greater than 5 (5,6,7,8 and 9) to its right, one is added to the rounding digit.
Jeff has to weigh 4.312 g sample of NaCl. To round off the underline number 4.<u>3</u>12, check for the digit right to it. It has 1, which is less than 5 thus according to the Rule 1, all the digits on right side of the rounding digit will drop out and the number gets rounded off to 4.3.
Therefore, 4.3 is most accurate measurement by Jeff.
