Silicon is the element having a mass of 28.09 g
<u>Explanation</u>:
- Silicon is the element having an atomic mass of 28.09 g / mol. So 28.09 g of silicon contains 6.023
10^23 atoms. One mole of each element can produce one mole of compound.
- The Atomic weight of an element can be determined by the number of protons and neutrons present in one atom of that element. So atomic weight expressed in grams always contain the same number of atoms( 6.023 10^23).
- Avagadro number is the number of atoms of 1 mole of any gas at standard temperature and pressure. It has been determined that 6.023 10^23 atoms of an element are equal to the average atomic mass of that element.
Cover with metal .Any elements other than hydrozen and helium concentration shows an absorbance
<span>Good Morning!
To measure the volume of an acid we use in the laboratory an instrument called burette (a). This instrument is used to calculate the volumes of chemical solutions. At first glance, these tools may be confused with syringes, but have different functions.
Hugs!</span>
The balanced chemical reaction for the complete combustion of C4H10 is shown below:
C4H10 + (3/2)O2 --> 4CO2 + 5H2O
The enthalpy of formation are listed below:
C4H10: -2876.9 kJ/mol
O2: none (because it is pure substance)
CO2: -393.5 kJ/mol
H2O: -285.8 kJ/mol
The enthalpy of combustion is computed by subtracting the total enthalpy formation of the reactants from that of the products.
ΔHc = (4)(-393.5 kJ/mol) + (5)(-285.8 kJ/mol) - (-2876.9 kJ/mol)
= -<em>126.1 kJ</em>
Thus, the enthalpy of combustion of the carbon is -126.1 kJ.
<u>Answer:</u> The correct answer is option A.
<u>Explanation:</u>
To calculate the volume of an object, we use the formula:
We are given:
Density of an object = 
Mass of an object = 8.2 grams
Volume of an object = ?
Putting values in above equation, we get:
Hence, the correct answer is Option A.
