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Both are compounds.
contains 1 carbon (C) atom and 2 oxygen (O) atoms.
It contains two different elements, so it is a COMPOUND.
is an IONIC compound with elements Sodium (Na) and Oxygen (O), which are different elements. Therefore, it is also a COMPOUND.
Answer:

Explanation:
We can use the Noyes-Whitney equation to calculate the rate of dissolution.

Data:
D = 1.75 × 10⁻⁷ cm²s⁻¹
A = 2.5 × 10³ cm²
Cₛ = 0.35 mg/mL
C = 2.1 × 10⁻⁴ mg/mL
d = 1.25 µm
Calculations:
Cₛ - C = (0.35 - 2.1 × 10⁻⁴) mg·cm⁻³ = 0.350 mg·cm⁻³
d = 1.25 µm = 1.25 × 10⁻⁶ m = 1.25 × 10⁻⁴ cm

Answer:
It is known that 1 mol of a molecule contains 6.023×1023 6.023 × 10 23 number of molecules. So, 0.25 moles of CO2 C O 2.
It is rinsed one last time with the solution to be measured because if there is water in the burret, then it could alter the results. Slightly, but it is still altering it.