Question

В соединение кремния с водородом массовая доля водорода равна 12, 5% . опредилите формулу этого соединения и валентности элиментов .

Answer 1

по формуле высшего определяем валентность элемента - 4,значит простейшее соединение с водородом будет иметь формулу ЭН4, 12,5:87,5=1:7(по мол массе),нужно умножить на 4 и получим 28 - это кремний

Answer 2

Determining the Formula of the Compound and Element Valencies

To determine the formula of the compound and the valencies of the elements, we can start by calculating the ratio of silicon to hydrogen in the compound based on the given mass percentage of hydrogen.

The mass percentage of hydrogen in the compound is 12.5%. This means that for every 100 grams of the compound, 12.5 grams are hydrogen.

Using this information, we can calculate the mass of silicon in the compound as follows:

- Mass of hydrogen = 12.5 grams - Mass of silicon = 100 - 12.5 = 87.5 grams

Now, we can calculate the ratio of silicon to hydrogen in the compound:

- Number of moles of hydrogen = (12.5 grams) / (1 g/mol) = 12.5 moles - Number of moles of silicon = (87.5 grams) / (28.0855 g/mol) = 3.115 moles

The ratio of silicon to hydrogen in the compound is approximately 3.115:12.5, which can be simplified to 1:4.

This indicates that the compound contains 1 atom of silicon for every 4 atoms of hydrogen.

Determining the Element Valencies

The valency of an element is the combining power of an element, or the number of hydrogen atoms with which one atom of the element can combine.

In the compound, the valency of silicon can be determined based on the ratio of silicon to hydrogen. Since there are 4 atoms of hydrogen for every 1 atom of silicon, the valency of silicon is 4.

Similarly, the valency of hydrogen can be determined based on the ratio. Since there is 1 atom of silicon for every 4 atoms of hydrogen, the valency of hydrogen is 1.

Therefore, the formula of the compound is SiH4, and the valencies of the elements are silicon (Si) with a valency of 4 and hydrogen (H) with a valency of 1.