This is why, at room temperature, iodine, which has the largest molecule, is a solid, bromine, which is the next in line in terms of size, is a liquid, and fluorine and chlorine, the smallest of the molecules, are both gases. So remember, nonpolar molecules only exhibit weak London dispersion forces.
For most women, the length of time between ovulation (when an egg is released from the ovary) and their monthly period is between 12 to 16 days (this is called the luteal phase). The first day of your menstrual cycle is the first day of your period (day 1). The period usually then lasts anything from 3 to 7 days. Youâll probably find that if you get any period pains, theyâll be at their worst in the first few days of your period.
When does ovulation happen? Regardless of how long or short your cycle normally is, ovulation usually occurs about 14 days before your next period starts (FPA 2014, NHS Choices 2016a). For example, say you have a regular 28-day menstrual cycle. Count the first day of your last period as day one. Your fertile window is likely to be around days 10 to 15. However, a lot of women have an irregular cycle. If this applies to you, the time from the first day of your last period to ovulation can vary from one month to the next (FPA 2014). What are the signs of ovulation? You can start to notice signs that youâre fertile about five days before you ovulate.