Answer:
109° 27'
Explanation:
The ammonium ion is tetrahedral in shape, all the HNH bonds are exactly at the tetrahedral bond angle since there are only bond pairs in the structure and no lone pairs. Recall that lone pairs decrease the bond angke from the ideal value in a tetrahedron due to higher repulsion.
Answer:
It's C
Explanation:
Most garnet found near Earth's surface forms when a sedimentary rock with a high aluminum content, such as shale, is subjected to heat and pressure intense enough to produce schist or gneiss.
It can uplift slowly due to the pressure of Earth’s plates.
It can melt into magma and recrystallize as extrusive igneous rock.
A mole of a substance is defined as: The mass of substance containing the same number of fundamental units as there are atoms in exactly 12.000g of 12C. Fundamental units change depending on the substance.
Answer:
pH = 2.18
Explanation:
Perchloric acid (HClO₄) is a strong acid. This means that in an aqueous solution it completely dissociates into H⁺ and ClO₄⁻ species.
First we <u>convert 249 mg HClO₄ into moles</u>, using its <em>molecular weight</em>:
- 249 mg HClO₄ ÷ 100.46 mg/mmol = 2.49 mmol HClO₄
<em>Because it is a strong acid</em>, 2.49 mmol HClO₄ = 2.49 mmol H⁺
We <u>calculate the molar concentration of H⁺</u>:
- 2.49 mmol H⁺ / 380 mL = 6.52x10⁻³ M
Finally we <u>calculate the pH of the solution</u>:
- pH = -log[H⁺] = -log(6.52x10⁻³)
