D. a change in color of a substance
<em>Answer:</em>
<em>B.) A hot liquid or air that expands, becomes less dense, and rises or becomes more dense and sinks.</em>
<em>Explanation:</em>
<em>Convention is the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat.</em>
Answer:
73.46839716589713698731965
Explanation:
Charge of nucleus is always positive whether it is element or isotope.
Answer:
mass of HNO₃ = 0.378 g
Explanation:
Normality = Molarity * number of equivalents
Molarity = Normality/number of equivalents
normality of HNO₃ = 0.30 N, Volume = 20 mL
HNO₃ ionizes in the following way:
HNO₃(aq) ----> H⁺ + NO₃⁻
Therefore, number of equivalents for HNO₃ is 1
molarity of HNO₃ = 0.30/1 =0.30 mol/dm³
Using the formula, molarity = number of moles/volume in liters
number of moles = molarity * volume
Number of moles of HNO₃ = 0.30 mol/dm³ * 20ml * 1 dm³ /1000 mL
number of moles = 0.006 moles
From the formula, mass = number of moles * molar mass
molar mass of HNO₃ = 63.0 g/mol
mass = 0.006 * 63
mass of HNO₃ = 0.378 g