Answer:
<u>= 48.077 kcal </u>
Explanation:
The balanced equation is :
Since the stoichiometric coefficient of Na2O = 1 hence its heat is
<u>-120 Kcal/mol</u> rather -120 Kcal only.
This means when 1 mole of the Na2O is burned , then 120 kcal of energy is released .
Molar mass of Na2O = 2(mass of Na) + 1(mass of O)
= 2(22.98)+16
=61.97 gram/mol
Molar mass = mass of the substance in grams present in 1 mole of it.
In 1 mole of Na2O , 61.97 gram of it is present.
Hence
61.97 gram of Na2O = -120 Kcal of heat is released
1 gram of Na2O =
So,
24.8 gram of Na2O will produce,
= -48.077 kcal of heat
You can also proceed through mole concept:
Calculate number of moles in 24.8 gram Na2O
Moles of Na2O = 24.08/61.9 = 0.4007 moles
So these many moles will produces:
0.4007 x 120
=-48.07
The answer is D. The cold fusion theory was first brought about by Stanley Pons and Martin Fleischmann in 1989. They claimed that their unintended experiment has produced enormous amounts energy at room temperatures that could only be explained by cold fusion theory. The experiment involved the electrolysis of heavy water (with deuterium rather than hydrogen isotope) on a palladium (Pd) electrode. Their claims had brought immense attention by scientists, however, subsequent replicative experiments attempts failed and some discredited the initial experiment.
Answer:
23892U=23490Th +42He
Explanation:
In alpha decay, the daughter nucleus is two units less than the parent in atomic number. The mass number also decreases by 4 units. The daughter is thus found two places before the parent in the periodic table.
Answer:
The correct answer is option C.Water molecules move throughout the solute
Explanation:
The basic standard for solute disintegration in a specific dissolvable is "like breaks up like". On account of water, a solute will disintegrate if it is polar. This is on the grounds that water is a polar dis-solvable. A polar substance is one which has particles that have a net charge on them. This net charge produces powers of fascination.
At the point when a polar solute is added to water, the water atoms are pulled in to the solute particles and they join to them. In the wake of appending to the water atoms, the solute particles are scattered all through the water. Accordingly, the appropriate response is particles or particles of a solute spread all through the water atoms.
<u>Answer:</u> The chemical symbol of the compound formed is 
or 
<u>Explanation:</u>
An ionic compound is formed when the complete transfer of electrons takes place from one element (usually metals) to another element (usually non-metals).
The element losing electron (metal) forms a positive ion known as a cation while the element gaining electron (non-metal) forms a negative ion known as an anion.
Element X has the atomic number 11 which is sodium. The electronic configuration of it is 
This element will lose 1 electron to form 
ion of 
Chlorine has the atomic number 17. The electronic configuration of it is 
This element will gain 1 electron to form 
ion
When these two ions combine, they lead to the formation of an ionic compound having a chemical formula of or
Hence, the chemical symbol of the compound formed is or
