Chemists, biologist, pharmacist, medical researcher ect…
When Ca(OH)₂ is added to a beaker of water the solution would turn phenolphthalein pink. Phenolphthalein is a common indicator and is only pink when in basic solutions. By adding calcium hydroxide, you are turning the solution into a basic solution since the concentration of OH⁻ ions is going up and therefore any phenolphthalein in solution would turn pink.
(answers A,C, and D would happen if you added an acid to the water such as HCl)
I hope this helps. Let me know if anything is unclear.
The radiator is next to the triangle, receiving the sound waves and they travel through the radiator up to the other room. She can't hear the sound if the triangle isn't struck near the radiator because the sound waves aren't going through the radiator, and are not able to reach her through the wall. Hope this helps!
The density of a glass helps determine the weight of the optical assembly and, along with lens diameter, becomes critical for weight sensitive applications.
Answer: 0.03798 kilograms
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number 
of particles.
To calculate the moles, we use the equation:
1 mole of chlorine gas 
weighs = 71 g
Thus 0.535 moles of chlorine gas will weigh = 
(1kg=1000g)
Thus there are 0.03798 kilograms in 12 L of chlorine gas.
