Can anyone teach me what is criss cross method in chemistry

Chemistry

1 answer:

Solnce55 [7]2 years ago

8 0

Answer:

In the criss-cross method, the numerical value of the ion charge of the two atoms are crossed over, which becomes the subscript of the other ion. Using this technique, we will write the chemical formula of the given compounds.

Criss cross the absolute values to give Al2O3. To find the formula for magnesium oxide:- The oxidation number of Mg is +2 and oxygen is -2. Criss cross the absolute values to give Mg2O2In this example there is a common factor of 2 so divide by 2 to give MgO.

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If the pH of a 1.00-in. rainfall over 1800 miles2 is 3.70, how many kilograms of sulfuric acid, H2SO4, are present, assuming tha

NARA [144]

There are 2.32 x 10^6 kg sulfuric acid in the rainfall.

Solution:
We can find the volume of the solution by the product of 1.00 in and 1800 miles2:
1800 miles2 * 2.59e+6 sq m / 1 sq mi = 4.662 x 10^9 sq m
1.00 in * 1 m / 39.3701 in = 0.0254 m
Volume = 4.662 x 10^9 m^2 * 0.0254 m
= 1.184 x 10^8 m^3 * 1000 L / 1 m3
= 1.184 x 10^11 Liters

We get the molarity of H2SO4 from the concentration of [H+] given by pH = 3.70:
[H+] = 10^-pH = 10^-3.7 = 0.000200 M
[H2SO4] = 0.000100 M

By multiplying the molarity of sulfuric acid by the volume of the solution, we can get the number of moles of sulfuric acid:
1.184 x 10^11 L * 0.000100 mol/L H2SO4 = 2.36 x 10^7 moles H2SO4

We can now calculate for the mass of sulfuric acid in the rainfall:
mass of H2SO4 = 2.36 x 10^7 moles * 98.079 g/mol
= 2.32 x 10^9 g * 1 kg / 1000 g
= 2.32 x 10^6 kg H2SO4

3 0

3 years ago

Read 2 more answers

What is the product of the reaction of hydrobromic acid and 2-bromo-1-butene in the presence of acid and ether?

sergejj [24]

Answer: The major product of the reaction between Hydrobromic Acid and 2-bromo-1-butene in the presence of ether and acid is 2,2-dibromobutane.

Explanation:

The mechanism of the reaction is supported by the Markovnikov's rule which explains that in the addition reaction of alkenes by hydrogen-halogen compounds, the incoming halogen substituent goes to the more substituted Carbon. It can also be stated that incoming hydrogen atom goes to the Carbon with more Hydrogen atoms.

The only case when the reverse of Markovnikov's rule takes place is when Hydrogen peroxide is present and the addition reagent is HBr.

This case is not like that and it simply follows the Markovnikov's rule.

I'll add an attachment of the reaction to this now.

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3 years ago

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A) What mass in grams of H20 is needed to react completely with 40.0 g of

Step2247 [10]

Answer:

$m_{H_2O}=9.24gH_2O$

Explanation:

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In this case, since there is a 2:2 mole ratio between sodium peroxide and water according to the given reaction, it is possible to apply the following stoichiometric setup for the calculation of the required mass of water:

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