1828 Berzelius introduce letters to symbolize elements. 1828 Berzelius introduce letters to symbolize elements

1828 Berzelius introduce letters to symbolize elements.

• 1828 Berzelius introduce letters to symbolize elements.

• 1829 Döbereiner devoloped “triads” groups of three elements with similar properties. Cl – Br - I, (the properties of Br are between Cl and I) Ca – Sr - Ba Li-Na-K

• 1864 Newlands arranged the known elements (around 60) in order tof atomic weights and observed similarities between the first and ninth elements, the second and tenth elements etc

• 1869 Lothar Mayer ve Dmitri Mendeleyev produced their periodic tables simultaneously

• 1896 William Ramsay discovered the noble gases.

• 1913 Henry Moseley, determined the atomic number of each of the elements.

Produced a table based on atomic weights and arranged periodically with elements with similar properties under each other. Left gaps for unknown elements and predicted their properties.

• Produced a table based on atomic weights and arranged periodically with elements with similar properties under each other. Left gaps for unknown elements and predicted their properties.

Elements are arrangednin the order of increasing atomic numbers and there is a periodic repitition of these elements.

• Elements are arrangednin the order of increasing atomic numbers and there is a periodic repitition of these elements.

• The basis of the periodic table is the electron configurations of the elements.

• Each horizontal row is called a a period.

• Each vertical column in the periodic atble is called a group. The chemical and physical proprties of the elements in a group are similar.

The boiling points of HCl and HI are : -84.9oC and -35.4oC respectively. Predict the boiling point of HBr?

• The boiling points of HCl and HI are : -84.9oC and -35.4oC respectively. Predict the boiling point of HBr?

• The boiling point of PH3 is : -87.4oC and the boiling point of SbH3 is: -17.1oC. Can you predict the boiling point of AsH3?

Li, K, Na

• Li, K, Na

• b) Se2-, Rb+, Br -

• c) O2-, F -, N 3-

Arrange the following elements in order of increasing first ionization energy.

• Arrange the following elements in order of increasing first ionization energy.

• i) 14Si, 16S , 12Mg

• ii) 8O, 9F, 16S

Calculate the molecular weight of CCl4

• Calculate the molecular weight of CCl4

• (C :12.01 Cl : 35.45)

• = (atomic weight of C) + (4 x atomic weight of Cl)

• = 12.01 + 4 x 35.45

• =153.8

Bileşiğin 100gramında ki elementlerin gram miktarını gösterir.

• Bileşiğin 100gramında ki elementlerin gram miktarını gösterir.

Elementlerin Bileşik içinde verilen kütle oranları mol sayısına çevirilir

• Elementlerin Bileşik içinde verilen kütle oranları mol sayısına çevirilir

• Herbir elementin mol sayısı, bulunan mol sayıları içindeki en küçük mol sayısına bölünür

• Elde edilen rakamlar ile basit formül yazılır (rakamlar tam sayı olmalıdır, bunun için uygun katsayı ile carpma yapılır)

Eğer bir bileşiğin basit formülü ve bileşiğin mol ağırlığı biliniyorsa, molekül formülü bulunabilir.

• Eğer bir bileşiğin basit formülü ve bileşiğin mol ağırlığı biliniyorsa, molekül formülü bulunabilir.

• Basit formülün ağırlığı x katsayı =

• mol ağırlığı