At dawn and dusk, large amount of blue and violet light(shorter wavelength) has been scattered so, the light that is recieved by an observer is mostly of a longer wavelength and therefore appears to be red.
The foods we eat, the air we breathe, cleaning chemicals, our emotions and literally every object that we can see or touch, love, jealousy, infatuation and all share in chemistry. For all living things to function and survive, their bodies perform various chemical processes.
zinc will react with sulphuric acid forming zinc sulphate dissolved in solution and releasing hydrogen gas.
Zn + conc. 2 H2SO4 ZnSO4 + SO2 + 2 H2O
Yes, a physical quantity can have magnitude and direction but still be a scalar if it doesn't obey the vector addition. An example is Electric Current which has magnitude and a fixed direction, but it does not follow vector laws of addition.

Quality of life refers to the overall well-being, satisfaction, and happiness that an individual or a community experiences in various aspects of their lives.