Answer:
See explanation
Explanation:
When a beaker of ethanoic acid is placed in the refrigerator, its temperature drops and the vessel feels cool.
Now, when we mix ethanoic acid and sodium carbonate, an endothermic reaction occurs, fizzing is observed as carbon dioxide is given off and heat is lost to the surroundings causing the reaction vessel to feel cool to touch.
The difference between putting ethanoic acid in the refrigerator and adding sodium carbonate to the solution is that, in the former, no new substance is formed. The substance remains ethanoic acid when retrieved from the refrigerator. In the later case, new substances are formed. The substance is no more ethanoic acid because a chemical reaction has taken place.
Answer is: mass number is 234.
Beta decay is radioactive decay<span> in which a </span>beta ray<span> and a </span>neutrino<span> are emitted from an </span><span>atomic nucleus.
</span>There are two types of beta decay: beta minus<span> and </span>beta plus. <span> In beta minus </span><span>decay, neutron is converted to a proton and an </span>electron<span> and an </span>electron antineutrino and in beta plus <span>decay, a proton is converted to a neutron and </span>positron<span> and an </span>electron neutrino, so mass number does not change.
Molarity can be defined as the number of moles of solute in 1 L of solution.
M = n/V
Where M is the molarity of the solution (M or mol/L), n is the moles of the solute (mol) and V is the volume of the solution (L).
Here, solute is KF.
n = <span>0.250 mol
</span>V = 0.500 L
M = ?
By applying the formula,
M = 0.250 mol / 0.500 L
M = 0.500 mol/L
Hence, the molarity of KF solution is 0.500 mol/L.
Answer:
A right? I'm pretty sure it's A
An hour is 60 minutes. So you multiple the hot by 60. You get 180 minutes plus the 75 remaining minutes. The answer is 255
