<h3>
Answer:</h3>
70.906 g
<h3>
Explanation:</h3>
We are given;
- Atoms of Chlorine = 1.2 × 10^24 atoms
We are required to calculate the mass of Chlorine
- We know that 1 mole of an element contains atoms equivalent to the Avogadro's number, 6.022 × 10^23.
- That is , 1 mole of an element = 6.022 × 10^23 atoms
- Therefore; 1 mole of Chlorine = 6.022 × 10^23 atoms
But since Chlorine gas is a molecule;
- 1 mole of Chlorine gas = 2 × 6.022 × 10^23 atoms
But, molar mass of Chlorine gas = 70.906 g/mol
Then;
70.906 g Of chlorine gas = 2 × 6.022 × 10^23 atoms
= 1.20 × 10^24 atoms
Thus;
For 1.2 × 10^24 atoms ;
= ( 70.906 g/mol × 1.2 × 10^24 atoms ) ÷ (1.20 × 10^24 atoms)
<h3>= 70.906 g </h3>
Therefore, 1.20 × 10^24 atoms of chlorine contains a mass of 70.906 g
=
<span>John Dalton introduced a theory proposing that elements vary because of the mass of their atoms.
He said in his theory that all matter is made up of indivisible blocks called atoms. He also stipulated in his theory that elements are identical thus, have different sizes and masses.
Dalton's theory was different from Niels Bohr who proposed a new atomic model which was also commonly known as the modern atomic theory. Bohr's theory says that atoms are arranged in circular orbits around the nucleus. He patterned his model as the solar system.
</span>
Answer:
The change in enthalpy is +210 kJ, so it is an endothermic reaction.
Explanation:
- The change in enthalpy shows that the reaction is exothermic or endothermic.
The change in enthalpy = The energy of products - the energy of reactants.
- If ΔH is positive value, the reaction is endothermic, the energy of the products is higher than that of the reactants.
- If ΔH is negative value, the reaction is exothermic, the energy of the products is lower than that of the reactants.
<em>For this reaction: </em>The change in enthalpy = The energy of products - the energy of reactants = 370 kJ - 160 kJ = + 210 kJ.
<em>So, the right choice is: The change in enthalpy is +210 kJ, so it is an endothermic reaction.</em>
It is B nevermind I thought it was c but it wasn't.
