How many atoms are in .00 × 10-10 g Au

1 answer:

6 0

Atomic mass Au = 196.96 u.m.a

196.96 g ----------- 6.02x10²³ atoms
0.00x10⁻¹⁰ g ------- ( atoms ? )

( 0.00 x10⁻¹⁰) x 6.02x10²³ / 196.96

0 / 196.96

= 0 atoms

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Answer:

[OH⁻] = 4.3 x 10⁻¹¹M in OH⁻ ions.

Explanation:

Assuming the source of the carbonate ion is from a Group IA carbonate salt (e.g.; Na₂CO₃), then 0.115M Na₂CO₃(aq) => 2(0.115)M Na⁺(aq) + 0.115M CO₃²⁻(aq). The 0.115M CO₃²⁻ then reacts with water to give 0.115M carbonic acid; H₂CO₃(aq) in equilibrium with H⁺(aq) and HCO₃⁻(aq) as the 1st ionization step.

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ΔC -x +x +x

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Hope this helps :)

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