Which chemical symbol describes an element? o H2O o 02 o CH4 o H2 SO4

Chemistry

2 answers:

ra1l [238]3 years ago

4 0

H20 is the answer to your question

navik [9.2K]3 years ago

4 0

Answer:

H20

Explanation:

. It is a symbol of water where H = Hydrogen, O = Oxygen and2 Elements in hydrogen and 1 element in oxygen;therefore its known as H2O.

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Which type of bonding is most important in ch3ch2ch2ch2ch2ch3?

saveliy_v [14]

The compound $CH_3CH_2CH_2CH_2CH_2CH_3$ is formed only by sharing of electrons between the atoms. The structure of the compound is shown in the image.

Each line between two atoms represents the sharing of an electron pair which results in the formation of a single bond. Since, carbon has 4 electrons in its valence shell and hydrogen has 1 electron in its valence shell so in order to complete the octet ( to have 8 electrons in their valence shell, noble gas configuration) to attain stability carbon needs 4 more electrons and hydrogen needs 1 electron. So, sharing of electron will occur as shown in the image and the formed compound is stable in nature.

Since, the bond that is formed by sharing of electrons between atoms is known as covalent bond. So, covalent bonding is most important in $CH_3CH_2CH_2CH_2CH_2CH_3$ .

7 0

4 years ago

How many moles are in 2.12g Cr2O3

ohaa [14]

Answer:

0.01395mol Cr2O3

Explanation:

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4 0

3 years ago

Calculate the standard reaction enthalpy for the reaction NO2(g) → NO(g) + O(g) given +142.7 kJ/mol for the standard enthalpy of

bulgar [2K]

Answer:

The standard reaction enthalpy for the given reaction is 235.15 kJ/mol.

Explanation:

$O_2(g) \rightarrow \frac{2}{3}O_3(g),\Delta H^o_{1}=142.7 kJ/mol$ ..[1]

$O_2(g) \rightarrow 2 O(g),\Delta H^o_{2}=498.4 kJ/mol$ ..[2]

$NO(g) + O_3(g)\rightarrow NO_2(g) + O_2(g) ,\Delta H^o_{3} = -200 kJ/mol$ ..[3]

$NO_2(g)\rightarrow NO(g) + O(g),\Delta H^o_{4}=?$ ..[4]

Using Hess's law:

Hess’s law of constant heat summation states that the amount of heat absorbed or evolved in a given chemical equation remains the same whether the process occurs in one step or several steps.

2 × [4] = [2]- (3 ) × [1] - (2) × [3]

$2\times \Delta H^o_{4}=\Delta H^o_{2} -3\times \Delta H^o_{1}-2\times \Delta H^o_{3}$