Answer:
The mass of 2,50 moles of NaCl is 146, 25 g.
Explanation:
First we calculate the mass of 1 mol of NaCl, starting from the atomic weights of Na and Cl obtained from the periodic table. Then we calculate the mass of 2.50 moles of compound, making a simple rule of three:
Weight NaCl= Weight Na + Weight Cl= 23 g+ 35,5 g= 58, 5 g/ mol
1 mol ------ 58, 5 g
2,5 mol---x= (2,5 mol x 58, 5 g)/ 1 mol = <u>146, 25 g</u>
T is amount after time t
<span>Ao is initial amount </span>
<span>t is time </span>
<span>HL is half life </span>
<span>log (At) = log [ Ao x (1/2)^(t/HL) ] </span>
<span>log (At) = log Ao + log (1/2)^(t/HL) </span>
<span>log (At) = log Ao + (t/HL) x log (1/2) </span>
<span>( log At - log Ao) / log (1/2) = t / HL </span>
<span>log (At/Ao) / log (1/2) = t / HL </span>
<span>HL = t / [( log (At / Ao)) / log (1/2) ] </span>
<span>HL = 14.4 s / [ ( log (12.5 / 50) / log (1/2) ] </span>
<span>HL = 14.4 s / 2 = 7.2 seconds </span>
You would know that the variable is quantitative if it shows any number to express the quantity. For example, quantitative variables are 50°C, 5 atm, 2 moles, 100 L and so on. A variable is qualitative if it expresses a relative quantity but not expressing a number. Examples would be: few, too hot, several, or even describing the characteristics of a variable. Hence, when the variable is in grams, then that would be quantitative.
Answer:
You didn't provide any statements. If it is an option, art is a form of expression. Something created from imagination that expresses the thoughts and emotions of the artist.