The correct answers are as follows:
1. MgSO4 + 2NH4OH = [NH4]2SO4 + Mg[OH]2.
This chemical equation implies that, one molecule of magnesium sulphate react with two molecules of ammonium hydroxide to give rise to one molecule of ammonium sulphate and one molecule of magnesium hydroxide.
2. The reaction between magnesium sulphate and ammonia is a DOUBLE REPLACEMENT REACTION.
A double replacement reaction is a type of reaction in which the two chemical substances which take part in the reaction switch their ions in such a way that two new products are formed. In the reaction of magnesium sulphate and ammonia, the magnesium sulphate gives its SO4 ion to ammonia and take the OH ion of the ammonia instead.
3. The epsom salt and the ammonia reacted. This is made obvious by the chemical reaction which was generated by their combination. On the edge of the penny used, one can see that there is a colour change, this shows that a chemical reaction occur.
From the equation:
4mol Li react with 1 mol O2
Molar mass Li = 7g/mol
mol in 84g Li = 84/7 = 12 mol Li
From the equation - 12 mol Li will react with 3 mol O2
At STP 1 mol O2 has volume = 22.4L
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At STP 3 mol O2 has volume = 3*22.4 = 67.2L O2 gas will react. </span>
Kinetic energy of an object can be expressed in terms of its mass m and velocity v as:
KE = 1/2 * m* v²
Thus higher the velocity, greater will be the Kinetic energy. Now, as the box moves along a ramp from top to bottom, its velocity increases and so does the KE. Hence, kinetic energy is maximum at the bottom
Ans B) at the bottom
Atomic mass Ca = 40 a.m.u
1 mole Ca ----------- 40 g
2.5 mols Ca -------- ( mass Ca )
Mass Ca = 2.5 x 40 / 1
Mass Ca = 100 / 1
= 100 g of Ca
hope this helps!
Answer:
oxygen is an element because it is a pure substance which cannot be split into simpler substances by chemical means
