The mortar and pestle is most commonly used in chemical laboratories or in the kitchen. Its key function is to grind the material into smaller pieces, usually into its powdered form. It looks like that shown in the picture. The mortar is the bowl in which the material to be pounded is placed, and the pestle does the pounding.
Now, when you ask if it can only pound one at a time, my honest answer is, it depends. Depending on the size of your mortar, you could grind materials two or three at a time. But if you are concerned with contamination, then you do it one at a time, especially if you don't want them to get mixed up.
Answer : The chemical formula for the compound is, 
Explanation :
When the element 'M' react with the
to give
.
The balanced chemical reaction is,

In this reaction, 'M' is in mono-atomic form and
is in diatomic form.
By the stoichiometry,
2 moles 'M' react with the 1 mole of
to give 2 moles of
.
Therefore, the chemical formula of the compound is, 
To evaluate the accuracy of a measurement, the measured value must be compared to the correct value. To evaluate the precision of a measurement, you must compare the values of two or more repeated measurements.
Answer:
8L
Explanation:
Using Boyle's law which states that the volume of a given mass of gas is inversely proportional to the pressure, provided temperature remains constant
P1V1= P2V2
P1 = 2atm, V1 = 12L ,
P2 = 3atm , V2 =
12 × 2 = V2 × 3
Divide both sides by 3
V2 = 24 ÷ 3
V2 = 8L
I hope this was helpful, please mark as brainliest
The mass of CO₂ gas produced during the combustion of one gallon of octane is 8.21 kg.
The given parameters:
- <em>Density of the octane, ρ = 0.703 g/ml</em>
- <em>Volume of octane, v = 3.79 liters</em>
<em />
The mass of the octane burnt is calculated as follows;

The combustion reaction of octane is given as;

From the reaction above:
228.46 g of octane -------------------> 704 g of CO₂ gas
2,664.37 of octane --------------------> ? of CO₂ gas

Thus, the mass of CO₂ gas produced during the combustion of one gallon of octane is 8.21 kg.
Learn more about combustion of organic compounds here: brainly.com/question/13272422