Im pretty sure it nitric acid
Answer: A. Limestone rocks dissolving in water
Explanation:
B: This is a physical change; it changes an object physically rather than chemically. It does not change the composition of the concrete, only the shape.
C: This is also a physical change because the water is just dragging sand with it, but not actually changing the composition of it.
D: Similar to option B, this is an example of physical weathering because the ice only divides the rock into different parts but doesn't change the composition or complexity of it.
The silicon wafer contains 20.96 g of silicon.
The mole of a substance is related to its mass and molar mass by the following equation:
<h3>Mole = mass / molar mass ....... (1)</h3>
Making mass the subject of the above equation, we have
<h3>Mass = mole × molar mass ..... (2)</h3>
With the above formula (i.e equation 2), we can obtain the mass of silicon in the wafer as follow:
Mole silicon = 0.746 mole
Molar mass of silicon = 28.09 g/mol
<h3>Mass of silicon =? </h3>
Mass = mole × molar mass
Mass = 0.746 × 28.09
<h3>Mass of silicon = 20.96 g</h3>
Therefore, the mass of silicon in the wafer is 20.96 g
Learn more: brainly.com/question/24639749
