Answer:
C. As scientists have learned more about chemicals, they have become more aware of their dangers
Explanation:
Chemicals are substances with standard compositions, held together by chemical bonds. Chemicals can exist in different phases such as solid, liquid, and gaseous phases. Over time, with a growing understanding of chemicals, their composition, and their reaction methods, scientists now have a better knowledge of the dangers chemicals can pose. To that effect, they have created standard safety measures for those who have to work with these chemicals.
When these guidelines are strictly adhered to, the chances of suffering accidents, burns, and explosions with these chemicals are significantly reduced.
Moles of lead(Pb) = 1.6x10^23/6.02x10^23 = 0.265 moles.
Weight of lead = moles x atomic weight of lead
= 0.265x207.2
= 54.908 grams.
Hope this helps!
Pressure in the submarine when the temperature is changed to 293 K is 108.9 K Pa
Explanation:
Pressure in the submarine = 108.9 kPa
Volume, V = 2.4 * 10^5 L
Pressure, P = 116k Pa
Temperature, T = 312 K
Ideal gas law: PV = nRT or n = PV / RT
So, moles of gas, n =116 KPa * 2.4 * 10 ^5L / 8.314 LK Pa K^-1 *312 K
= 1.073 *10^4 mol
when temperature is changed to 293K,
PV = nRT or P = nRT / V
=1.073 *10^4 mol *8.314 LK Pa mol^-1 K^-1 *293 K / 2.4*10^5L
=108.9 K Pa
Pressure in the submarine when the temperature is changed to 293 K is 108.9 K Pa
Answer:
Both roots are imaginary roots.
Explanation:
Consider these things:
If we try to solve x²+1 = 0, notice that we aren't able to solve the equation in Real Number system because there are no negative outputs for quadratic function.
Remember that quadratic function has range greater or equal to the max-min value.
x-axis plane represents the solutions of that equation. If a graph intersects x-axis plane then it has a solution.
While a graph that doesn't have any intersects on x-plane, it means that the equation for that graph doesn't have real solutions but imaginary solutions.
As you may notice some of parabola graph has one intersect, two intersects or none. One intersect is one solution to the equation — Two intersects are two solutions of the equation and lastly, no intersects mean that no real solutions and remain only imaginary solution.
