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3 years ago

Use the crossover method to find the chemical formula of a calcium oxide

Chemistry

1 answer:

Dovator [93]3 years ago

3 0

Answer:

CaO

how:

since its an iconic compound (metal(Ca)+non-metal(O)=iconic(CaO) we have to take account the charges

so;

$Ca^{+2}$ $O^{-2}$

now we will cross them

$Ca_{2} O_{2}$

since both the values are same will cross it out.

hence: CaO

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¿Cuántos lunares hay en 1,035 gramos plomo

SpyIntel [72]

Answer:

TERO BAU KO CHAK

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3 years ago

Read 2 more answers

The Cabbage Indicator

Masja [62]

.A solution that serves as a pH indicator may be made using red cabbage, which is frequently available in homes. In essence, the color of the cabbage depends on the acidity of the solution and a pigment molecule called flavin or anthocyanin.

To determine whether a material is an acid or a base, red cabbage indicator is a purple-colored solution

Vinegar is an acid and its pH value is less than 7 and hence

Red color is produced

Baking soda is base and its pH value is greater than 7 and between 8-9

and the color produced is sky blue

Bleach is the green which is also a basic and because the pH value is 10-11

Householder cleaner is having pH 11-13 which is basic and hence the yellow is the color of household cleaner .

A basic solution goes away from being basic and toward the center of the pH scale when an acid is introduced. The base is "neutralized" in this manner.

Learn more about pH value here

brainly.com/question/19584961

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3 0

1 year ago

how many kilograms of a 35% m/m sodium chlorate solution is needed to react completely with 0.29 l of a 22% m/v aluminum nitrate

Stolb23 [73]

Answer:- 0.273 kg

Solution:- A double replacement reaction takes place. The balanced equation is:

$3NaClO_3+Al(NO_3)_3\rightarrow 3NaNO_3+Al(ClO_3)_3$

We have 0.29 L of 22% m/v aluminum nitrate solution. m/s stands for mass by volume. 22% m/v aluminium nitrate solution means 22 g of it are present in 100 mL solution. With this information, we can calculate the grams of aluminum nitrate present in 0.29 L.

$0.29L(\frac{1000mL}{1L})(\frac{22g}{100mL})$

= 63.8 g aluminum nitrate

From balanced equation, there is 1:3 mol ratio between aluminum nitrate and sodium chlorate. We will convert grams of aluminum nitrate to moles and then on multiplying it by mol ratio we get the moles of sodium chlorate that could further be converted to grams.

We need molar masses for the calculations, Molar mass of sodium chlorate is 106.44 gram per mole and molar mass of aluminum nitrate is 212.99 gram per mole.

$63.8gAl(NO_3)_3(\frac{1mol}{212.99g})(\frac{3molNaClO_3}{1molAl(NO_3)_3})(\frac{106.44g}{1mol})$

= $95.7gNaClO_3$

sodium chlorate solution is 35% m/m. This means 35 g of sodium chlorate are present in 100 g solution. From here, we can calculate the mass of the solution that will contain 95.7 g of sodium chlorate and then the grams are converted to kg.

$95.7gNaClO_3(\frac{100gSolution}{35gNaClO_3})(\frac{1kg}{1000g})$

= 0.273 kg

So, 0.273 kg of 35% m/m sodium chlorate solution are required.

7 0

3 years ago

Which of the following shows an accurate combustion reaction?

Jet001 [13]

Answer:

Cu + O₂ → CuO₂

Explanation:

A combustion reaction is the reaction with oxygen along with the release of energy in form of heat or light.

Organic compounds (like CH₄) undergo combustion forming water and CO₂.

The combustion reaction of CH₄ is:

CH₄ + 2O₂ → CO₂ + 2H₂O

Hence, the first equation from the choices is not showing the combustion reaction of CH₄.

Not only organic compounds can undergo combustion. Metals and no metals can undergo combustion, i.e. metals and no metals can react with oxygen releasing light or heat.

The reaction of copper and oxygen (second choice) is a combustion reaction:

Cu + O₂ → CuO₂

The formation of water (2H₂ + O₂ → 2H₂O) is other example of a combustion reaction where no organic compounds are involved.

On the other hand, the other two equations from the choice list are not reactions with oxygen, so they do not show combustion reactions.

5 0

3 years ago

52.1 mL of aqueous 0.255 M Pb(NO3)2 is mixed with 38.5 mL of 0.415 M NaCl. The equation for the precipitate reaction is: Pb(NO3)

Elan Coil [88]

Answer:

0.0585 M

Explanation:

Pb(NO₃)₂ (aq) + 2NaCl (aq) → PbCl₂ (s) + 2NaNO₃ (aq)

First we calculate the inital number of moles of each reagent, using the given volumes and concentrations:

0.255 M Pb(NO₃)₂ * 52.1 mL = 13.3 mmol Pb(NO₃)₂

0.415 M NaCl * 38.5 mL = 16.0 mmol NaCl

Then we calculate how many Pb(NO₃)₂ moles reacted with 16.0 mmoles of NaCl, using the stoichiometric coefficients of the reaction:

16.0 mmol NaCl * $\frac{1mmolPb(NO_3)_2}{2mmolNaCl}$ = 8.00 mmol Pb(NO₃)₂

Now we calculate the remaining number of Pb(NO₃)₂ moles after the reaction:

13.3 mmol - 8.00 mmol = 5.30 mmol Pb(NO₃)₂

Finally we divide the number of moles by the final volume to calculate the concentration:

5.30 mmol / (52.1 mL + 38.5 mL) = 0.0585 M

6 0

2 years ago