Physical changes only affect the appearance of an object. While chemical happens to the chemical make up and cannot be reversed. Think of it this way- physical change is like hair tint , it wears off- chemical is like permanent hair dye, it's permanent.
Answer:
MedlinePlus Drugs Information
Explanation:
Promethazine is in a class of medication called phenothiazines
Answer:
Explanation:
Earth's atmosphere is composed of about 78% nitrogen, 21% oxygen, and one percent other gases. These gases are found in layers (troposphere, stratosphere, mesosphere, thermosphere, and exosphere) defined by unique features such as temperature and pressure.
Three states of matter
Solids, liquids and gases are three states of matter. In solids, the particles are tightly packed together. In liquids, the particles have more movement, while in gases, they are spread out. Particles in chemistry can be atoms, ions or molecules.
It is important to understand the particle nature of matter. The particles that make up matter are not ‘small bits of solid’ or ‘small drops of liquid’ but atoms and molecules. The physical characteristics of those atoms and molecules decide its state.
Fe2O3 + 3CO --------> 2Fe + CO2
1 : 3 : 2 : 3
13.3 <--- 40 ------> 26.6 ---> 40 ( mol)
n = m/M
m CO2 = n.M = 13.3 . 40 = 532 ( g)
p/s : i hope that this will help ( cause i'm not really good at english :}}} )
