<span>Endothermic reactions take in heat from the environment in order to react while exothermic reactions release heat during the reaction. For this, D must be true as the products have less energy because they have released heat during the reaction. A and C are incorrect because they products and reactants are equal and B is wrong because the energy of the products would be more as the reaction took in heat.</span>
Answer:
The answer is 10 degrees celsius
Explanation:
Covalent bonds but not ionic
Answer:
Option a: positron emission.
Explanation:
In the transformation we have:
⁶⁷Ga → ⁶⁷Zn
The reaction is:

For Ga to become Zn, the atom nucleus has to lose a proton, so in the given options, the reaction that involves the transformation of a proton is the option a, positron emission.
In a positron emission, a proton becomes into a neutron and a positron:

Therefore, the correct answer is option a: positron emission.
I hope it helps you!
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
<span>
At STP 3 mol O2 has volume = 3*22.4 = 67.2L O2 gas will react. </span>