<h3>
Answer:</h3>
915 Joules
<h3>
Explanation:</h3>
- The heat of fusion is the heat that is required to convert a given mass of a substance from solid state to liquid state without change in temperature.
- In this case, we are given specific heat of a substance as 122 joules per gram
- It means that amount of heat equivalent to 122 joules is required to change 1 gram of the substance from solid state to liquid state.
- Therefore, we can determine the amount of heat needed to change 7.5 grams of the substance from solid to liquid state.
1 g = 122 Joules
7.5 g = ?
= 122 × 7.5
= 915 Joules
Thus, 7.5 g of the substance at its melting point will require 915 Joules of heat to melt.
Answer:
Erythrocytes
Erythrocytes do not contain a nucleus. This would make answer choice "A" correct. Erythrocytes are red blood cells and these cells differ from the other cells of the body because of the absence of the nucleus. All the other cells noted have nuclei.
Explanation:
Have A Wonderful Day !!
Answer: 66.2 g
Explanation:
1) The ratio of Al in the molecule is 1 mol to 1 mol .
2) The mass of 1 mol of molecules of Al (CH2H3O2)3 is the molar mass of the compound.
3) You calculate the molar mass of the compound using the atomic masses of each atom, in this way:
Al: 27 g/mol
C: 2 * 3 * 12 g/mol = 72 g/mol
H: 3 * 3 * 1 g/mol = 9 g/mol
O: 2 * 3 * 16 g/mol = 96 g/mol
Molar mass = 27 g/mol + 72 g/mol + 9 g/mol + 96 g/mol = 204 g/mol
4) Set a proportion:
27 g/mol x
-------------------- = ----------
204 g/mol 500 g
5) Solve for x:
x = 500 g * 27 g/mol / 204 g/mol = 66.2 g
Answer: sodium amide undergoes an acid -base reaction
Explanation:
sodium amide is a ionic compound and basically exists as sodium cation and amide anion. Amide anion is highly basic in nature and hence as soon as there is amide anion generated in the solution , Due to its very pronounced acidity it very quickly abstracts the slightly acidic proton available on methanol.
This leads to formation of ammonia and sodium methoxide.
Hence sodium amide reacts with methanol and abstracts its only acidic proton and form ammonia and sodium Methoxide.
Hence the 3rd statement is a corrects statement.
So we cannot use methanol for sodium amide because sodium amide itself would react with methanol and the inherent molecular natur of sodium amide would then change.
The 1st and 2nd statements both are incorrect because both the compounds methanol as well as sodium amide have dipole moments and hence are polar molecules.
The 4th statement is also incorrect as both the molecules have dipole moment and hence there would be ion-dipole forces operating between them.
The following reaction occurs:
NaNH₂+CH₃OH→NH₃+CH₃ONa