When a tortilla alone can run you 300 calories, and a dollop of sour cream about 115, staying under 1000 can be challenging (forget about adding chips and guacamole). The Times found that just 25 out of 1,200 burritos fell below 700 calories.
the hydrogen atom attracts electrons much more strongly than the oxygen atom. water has two hydrogen atoms covalently bonded to a single oxygen atom. the oxygen atom has a greater attraction for electrons than the hydrogen atom does. water dipole moment is equal to zero. the electrons of the covalent bond are not shared equally between the hydrogen and oxygen atoms.
has a value close to 10â14 at 25 Â°C, so the concentration of hydroxide ions in pure water is close to 10â7 molâdmâ3, in order to satisfy the equal charge constraint. The pH of a solution is equal to the decimal cologarithm of the hydrogen cation concentration; the pH of pure water is close to 7 at ambient temperatures. The concentration of hydroxide ions can be expressed in terms of pOH, which is close to 14 â pH, so pOH of pure water is also close to 7.