In order to grasp the concept of molar mass calculations it is important to understand the molar unit. The mole also called mol is the basic unit of measurement in chemistry. By definition, in modern chemistry, one mole represents the number of carbon atoms in exactly 12 grams of carbon 12 isotope.
Fetal development during the first trimester. The most dramatic changes and development for your baby occur during the first trimester. Itâs also during this time that the fetus is the most susceptible to damage from alcohol, drugs, certain medications, and illnesses.
The second trimester is weeks 13 to 27, and the third trimester starts about 28 weeks and lasts until birth. This slide show will discuss what occurs to both the mother and baby during each trimester. First Trimester