The synthesis of a compound from its elements in their standard state, accompanied by a change in energy that is known as standard enthalpy of formation of a compound. The standard state of a substance is the most stable physical state of the compound that exist at STP that is at 1 atm, 273 K temperature. So the answer is yes, the energy change accompanying the synthesis of a compound from its elements in their standard state.
<h2>
Which source would be most reliable for gathering experimental results related to a new compound’s molecular mass : A textbook that lists molecular masses of similar compounds</h2>
Explanation:
Atom:
It is a smallest particle of an element which may as may not have independent existence.
The are very small in size.
Their size is measured in unit nm (nanometer)
1nm – 10⁻⁹ m.
hydrogen atom is smallest of all size is only 10⁻¹⁰ nm
Atoms are represented by symbols (given by berzelius )
Atomic mass of element-
Active atomic mass of atom can’t be measured but relative atomic mass can be known.
I.e. relative atomic mass of an atom of element is defined as average relative mass of atom as compared with atom of 612c taken as 12u.
Atomic mass – no. Of times one atom of he element is heavier then 1/12th of c atom.
Molecule
It is smallest particle of an element or compound which is able to exist independently.
Some element exist as
Diatomic molecuel eq:- O₂
Triatomic molecule eq:- O₃
¬
So,
Atomicity – is no. of atoms in a molecule of an element.
Some more examples:- phosphorous P4 (tetra atomic)
sulphur S8 (poly-atomic)
nitrogen N2 (diatomic)
Molecular mass
It is the mass of molecule that is obtained by adding masses of atoms multiplied with number of atoms of each type .
Answer:
<h2>18 g/mL</h2>
Explanation:
The density of a substance can be found by using the formula
volume = final volume of water - initial volume of water
volume = 62 - 52 = 10 mL
From the question we have
We have the final answer as
<h3>18 g/mL</h3>
Hope this helps you
The amount of energy is constant, but it is converted from one form to another.
Depends how many sig figs you are rounding to so I won't round to tenth or hundredth but the answer is 2.037 * 10^7