Answer:
An atomic number
Explanation:
If a neutral atom has 30 protons and 34 neutrons, the number of electrons in the atom is: A) 94. B) 34. 64. ... 17) What is the symbol for the ion with 19 protons and 18 electrons? A) F+. B) K+ ... 21) Identify the metalloid in the following list. Hope this helps you! Ask me anything if you have any quistions!
Answer:
3
Explanation:
Zeros to the right of a decimal point after a value are sigificant, The leading zeros to reach the first digit ("1") are not. This has 3 sig figs: 120
<h3>
Answer:</h3>
0.248 g
<h3>
Explanation:</h3>
<u>We are given;</u>
- Time as 40 minutes
- Original amount of N-13
We are required to calculate the amount left after decay.
- We need to know the half life of N-13 first;
- Half life of N-13 is 9 minutes 58 seconds (9.965 minutes0
We are going to use the formula;
- Remaining amount = Original amount × 0.5^n
That is; N = N₀ × 0.5^n , where n is the number of half lives.
n = 40 minutes ÷ 9.965 minutes
= 4.014
Therefore;
N = 4 g × 0.5^4.014
= 0.248 g
Therefore, the mass of Nitrogen-13 that will be left is 0.248 g
Gold (III) nitrate in an aqueous solution is hydrolyzed with formation of gold (III) metahydroxide.
Au(NO₃)₃ → Au³⁺(aq) + 3NO₃⁻(aq)
Au³⁺ + H₂O ⇄ AuOH²⁺ + H⁺
AuOH²⁺ + H₂O ⇄ Au(OH)₂⁺ + H⁺
Au(OH)₂⁺ + H₂O → AuOOH·H₂O(s) + H⁺
Au(NO₃)₃(aq) + 2H₂O(l) = AuOOH(s) + 3HNO₃(aq)
