Identify the arrows that represent the process of cooling. gas liquid

1. _____ represents a formula for a chemical compound. A.H B.C C.P D.H2O

Drupady [299]

H2O represents a chemical compound

5 0

3 years ago

Write the balanced chemical equation for the following reaction. Phases are optional. Solid calcium chlorate decomposes to form

Tanya [424]

Answer:

Ca(ClO₃)₂ (s) → CaCl₂ (s) + 3O₂ (g)

Explanation:

1) Word equation (given)

calcium chlorate (solid) → solid calcium chloride (solid) + oxygen (gas)

2) Chemical formulae of the reactant and products:

Calcium chlorate:

The most common oxidation states of chlorine are -1, +1, +3, +5, +7.

The suffix ate in chlorate means that chlorine atom is with the third lowest oxidation state (counting only the positive states). So, this is +5.

The oxidation state of calcium is +2.

Hence, the chemical formula of calcium chlorate is Ca(ClO₃)₂

Calcium chloride

The suffix ide in chloride means that chlorine is with oxidation state -1. Again the oxidation state of calcium is +2.

Hence, the chemical formula of calcium chloride is CaCl₂

Oxygen

Oxygen gas is a diatomic molecule, so its chemical formula is O₂.

Phases

The symbols s and g (in parenthesis) indicate the solid and gas phases respectively.

3) Chemical equation:

Ca(ClO₃)₂ (s) → CaCl₂ (s) + O₂ (g)

That equation is not balanced becasue the number of O atoms in the reactant side and in the product side are different.

4) Balanced chemical equation:

Add a 3 as coefficient in front of O₂(g), in the product side to balance:

Ca(ClO₃)₂ (s) → CaCl₂ (s) + 3O₂ (g)

Verify that all the atoms are balanced:

Atom Reactant side Product side

Ca 1 1

Cl 2 2

O 3×2 = 6 2×3 = 6

Conclusion: the equation is balanced and the final answer is:

Ca(ClO₃)₂ (s) → CaCl₂ (s) + 3O₂ (g)

5 0

3 years ago

Choose the element that IS NOT in the same period as Potassium.

Lesechka [4]

E. sodium is the answer

8 0

3 years ago

At a certain temperature, the solubility of n2 gas in water at 3.08 atm is 72.5 mg of n2 gas/100 g water . calculate the solubil

8090 [49]

According to Henry's law, solubility of solution is directly proportional to partial pressure thus,

$\frac{S_{1}}{P_{1}}=\frac{S_{2}}{P_{2}}$

Solubility at pressure 3.08 atm is 72.5/100, solubility at pressure 8 atm should be calculated.

Putting the values in equation:

$\frac{0.725}{3.08}=\frac{S_{2}}{8}$

On rearranging,

$S_{2}=\frac{0.725\times 8}{3.08}=1.88$

Therefore, solubility will be 1.88 mg of $N_{2}$ gas in 1 g of water or, 188 mg of tex]N_{2}[/tex] gas in 100 g of water.

3 0

3 years ago

. A bright violet line occurs at 435.8 nm in the emission spectrum of mercury vapor. What amount of energy, in joules, must be r

Tom [10]

Answer : The energy released by an electron in a mercury atom to produce a photon of this light must be, $4.56\times 10^{-19}J$

Explanation : Given,

Wavelength = $435.8nm=435.8\times 10^{-9}m$

conversion used : $1nm=10^{-9}m$

Formula used :

$E=h\times \nu$

As, $\nu=\frac{c}{\lambda}$

So, $E=h\times \frac{c}{\lambda}$

where,

$\nu$ = frequency

h = Planck's constant = $6.626\times 10^{-34}Js$

$\lambda$ = wavelength = $435.8\times 10^{-9}m$

c = speed of light = $3\times 10^8m/s$

Now put all the given values in the above formula, we get:

$E=(6.626\times 10^{-34}Js)\times \frac{(3\times 10^{8}m/s)}{(435.8\times 10^{-9}m)}$

$E=4.56\times 10^{-19}J$

Therefore, the energy released by an electron in a mercury atom to produce a photon of this light must be, $4.56\times 10^{-19}J$

3 0

3 years ago