Atomic Number definition: The number of protons within the nucleus of x atom.
Atomic Mass definition: The number of protons and/+ neutrons within the nucleus of x atom.
The given information states that the element has 8 protons and 8 neutrons in its nuclei with 8 electrons revolving around it. If the atomic number is 'the number of protons' and we have 8 given protons, our answer would be 8. If the atomic mass is protons + neutrons and we have 8 protons and neutrons, our answer for atomic mass would inevitably be 16.
Therefore
Atomic number: 8
Atomic mass: 16
Answer:
Explanation:
48.16%
Well, both abundances have to total 100% so is Ag-107 is 51.84%, then Ag-109 must be 100 – 51.84 = 48.16%.
Hope This Helps :)
Answer:
Just ask google for help
Explanation:
I always do it and get it right
Answer:
Oiling is done on a regular basis to sewing Machine because in the machine there are lots of machinery parts i.e. wheels and axels, etc. which are in continuous use and they possess so much frictional force between them that wear tear may be observed in those parts.
Answer:
- <u><em>It is positive when the bonds of the product store more energy than those of the reactants.</em></u>
Explanation:
The <em>standard enthalpy of formation</em>, <em>ΔHf</em>, is defined as the energy required to form 1 mole of a substance from its contituent elements under standard conditions of pressure and temperature.
Then, per defintion, when the elements are already at their standard states, there is not energy involved to form them from that very state; this is, the standard enthalpy of formation of the elements in their standard states is zero.
It is not zero for the compounds in its standard state, because energy should be released or absorbed to form the compounds from their consituent elements. Thus, the first choice is false.
When the bonds of the products store more energy than the those of the reactants, the difference is:
- ΔHf = ΔHf products - ΔHf reactants > 0, meaning that ΔHf is positive. Hence, the second statement is true.
Third is false because forming the compounds may require to use (absorb) or release (produce) energy, which means that ΔHf could be positive or negative.
Fourth statement is false, because the standard state of many elements is not liquid. For example, it is required to supply energy to iron to make it liquid. Thus, the enthalpy of formation of iron in liquid state is not zero.
