Answer:
The empirical formula for the compound is Na2O
Explanation:
Data obtained from the question include:
Sodium (Na) = 74.2g
Oxygen (O) = 25.8g
We can obtain the empirical formula for the compound as follow:
First, divide the above by their individual molar mass as shown below:
Na = 74.2/23 = 3.226
O = 25.8/16 = 1.613
Next, divide the above by the smallest number
Na = 3.226/1.613 = 2
O = 1.613/1.613 = 1
Therefore, the empirical formula is:
Na2O
The minerals that one might be examining if you place some hydrochloric acid on a sample and it fizzes are Calcite and Dolomite.
Calcite and dolomite are very similar minerals. Both have the same hardness, the same rhombohedral cleavage, and are found in identical geologic settings. The best way to tell one from the other is the acid test; A drop of 1 M HCl on calcite produces an instant , obvious Fizz; a drop on dolomite produces slow or no obvious bubbling.
The sign's glass absorbed 25466.7 J
<h3>
Further explanation</h3>
Given
The temperature of glass : 23.5 °C to 65.5 °C
mass = 905 g
the specific heat capacity = 0.67 J/g °C
Required
Heat absorbed
Solution
Heat absorbed by sign's glass can be formulated :

ΔT=65.5 - 23.5 = 42
