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3 years ago

Below is a picture of the inner workings of a lava lamp. It consists of a glass 1 point

1 answer:

8 0

Heat within the asthenosphere creates convection currents (similar to the currents that can be seen in the lava lamp). These convection currents cause the tectonic plates to move several centimeters per year relative to each other.

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Please help! Even if you only know one answer, it still helps. Describe the uses of the following safety equipment:

meriva

Answer:

eye wash: if you get chemicals in your eyes it helps to clean it

chemical/safety shower; If chemical gets on your skin everywhere you need to take a shower immediately so it helps you get rid of the chemicals on your skin

fire extinguisher: if something cashes on fire you need that to extenguish it

Explanation:

8 0

3 years ago

In pure water at 25 °C, the concentration of a saturated solution of CuF2 is 7.4 × 10−3 M. If measured at the same temperature,

Romashka-Z-Leto [24]

Answer:

The concentration of a saturated solution of CuF₂ in aqueous 0.20 M NaF is 4.0×10⁻⁵ M.

Explanation:

Consider the ICE take for the solubility of the solid, CuF₂ as:

CuF₂ ⇄ Cu²⁺ + 2F⁻

At t=0 x - -

At t =equilibrium (x-s) s 2s

The expression for Solubility product for CuF₂ is:

$K_{sp}=\left [ Cu^{2+} \right ]\left [ F^- \right ]^2$

$K_{sp}=s\times {2s}^2$

$K_{sp}=4s^3$

Given s = 7.4×10⁻³ M

So, Ksp is:

$K_{sp}=4\times (7.4\times 10^{-3})^3$

Ksp = 1.6209×10⁻⁶

Now, we have to calculate the solubility of CuF₂ in NaF.

Thus, NaF already contain 0.20 M F⁻ ions

Consider the ICE take for the solubility of the solid, CuF₂ in NaFas:

CuF₂ ⇄ Cu²⁺ + 2F⁻

At t=0 x - 0.20

At t =equilibrium (x-s') s' 0.20+2s'

The expression for Solubility product for CuF₂ is:

$K_{sp}=\left [ Cu^{2+} \right ]\left [ F^- \right ]^2$

$1.6209\times 10^{-6}={s}'\times ({0.20+2{s}'})^2$

Solving for s', we get

<u>The concentration of a saturated solution of CuF₂ in aqueous 0.20 M NaF is 4.0×10⁻⁵ M.</u>

3 0

4 years ago

write a chemical equation for the ionization of water. how do you indicate that this is a reversible action?

LiRa [457]

H₂O + H₂O ⇌ H₃O⁺ + OH⁻

You use two single-barbed arrows pointing in opposite directions (technically rightwards harpoon over leftwards harpoon) <em>to indicate a reversible reactio</em>n.

8 0

4 years ago

If a chemical with a toxicity level of 1 is mixed with a different chemical with a toxicity level of 1, the combined effect of e

ollegr [7]

Answer:

c. antagonism

Explanation:

The toxic effect is that produced by one or several toxic agents on an organism, population or community that is manifested by biological changes. Its degree is assessed by an intensity or severity scale and its magnitude is related to the dose (amount of substance administered, usually expressed per unit of body weight) or the concentration (substance applied in the medium) of the toxic agent.

The effect can be:

- Quantum: consisting of the presence or absence of a characteristic (eg death or existence of tumors).

- Lethal: death by direct action as a result of exposure to a certain concentration of a toxic agent.

- Sublethal: occurs below the level that causes death as a direct result of exposure to a certain concentration of a toxic agent.

- Acute: that caused by the action of chemical substances on living organisms, which manifests rapidly and severely (after a short period of exposure: 0 - 96 h, typically.).

- Chronic: one that occurs, in general, after a prolonged period of exposure (usually manifests after days or years, depending on the species).

- Additive: the magnitude of the effect or simultaneous response of two or more substances is equal to the sum of the effects or responses of each.

- Combined: when two or more substances applied at the same time produce different effects or have different modes of action.

- Enhancement or synergism: when the toxicity of a mixture of chemical agents is greater than expected by the simple sum of the toxicities of the individual agents present in the mixture.

- Inhibition or antagonism: when the toxicity of a mixture of chemical agents is lower than expected by the simple sum of the toxicities of the individual agents present in the mixture.

7 0

4 years ago

what mass of copper is produce when Zinc is added to a solution containing 31.9g copper (ii) tetraoxosulphate (vi)

Sergio [31]

12.7 grams of copper will be produced.

<h3><u>Explanation</u>:</h3>

Copper is placed below zinc in the metal activity series. This means zinc can replace copper from its salt. Here zinc is added to the salt solution of copper sulphate. The reaction involved is

CuSO4 +Zn =ZnSO4 +Cu.

Zinc sulphate is soluble in the solution and rose red copper will be precipitated from the solution.

From the chemical equation we can see that 1 mole of zinc replaces 1 mole of copper. As no mass of zinc added is mentioned we will assume that excess of zinc is added.

Atomic mass of copper = 63.5

Atomic mass of sulphur = 32.

Atomic mass of oxygen = 16.

So molecular mass of copper sulphate = $63.5 + 32 + 4\times16$ = 159.5.

So, mass of 1 mole of copper sulphate is 159.5 grams.

So, in 31.9 grams of copper sulphate, number of moles of copper sulphate present = $\frac {159.5}{31.9}$ = 0.2

In 1 mole of copper sulphate, 1 mole of copper is present.

So in 0.2 moles of copper sulphate, 0.2 moles of copper is present.

So mass of 0.2 moles of copper = $0.2\times63.5$ = 12.7 grams

8 0

4 years ago