Answer:
A. When water moves into a crack and freezes, it expands and forces the crack wider.
Explanation:
A crack in a rock can fill with water which then freezes as the temperature drops. As the ice expands, it pushes the crack apart, making the crack larger. When the temperature rises again, the ice melts, and the water fills the newer parts of the crack. Once the water freezes again when the temperature drops, the expansion of the ice causes further expansion to the crack.
Answer;
K+ and NO3- ions
Explanation;
The main ions remaining are K+ and NO3- ions after pbi2 precipitation is complete.
However; There will always be tiny amounts of Pb2+ and I- ions, but most of them are in the solid precipitate.
Answer:
D.
Explanation:
You try to get 8 electron on the outermost "shell" so you have no left over or "valence" electrons.
Answer:
7.89 g
Explanation:
Step 1: Write the balanced equation
S₈ + 16 F₂(g) → 8 SF₄
Step 2: Calculate the moles corresponding to 2.34 g of S₈
The molar mass of S₈ is 256.52 g/mol.

Step 3: Calculate the moles of SF₄ produced from 9.12 × 10⁻³ mol of S₈
The molar ratio of S₈ to SF₄ is 1:8. The moles of SF₄ produced are 8/1 × 9.12 × 10⁻³ mol = 0.0730 mol
Step 4: Calculate the mass corresponding to 0.0730 moles of SF₄
The molar mass of SF₄ is 108.07 g/mol.
