Mercury thermometers work because mercury ___

Describe the importance of the water cycle in the terms of;

nikitadnepr [17]

Answer:

ii.

Explanation:

Regulating weather patterns

3 0

2 years ago

The half life for the decay of carbon- is years. Suppose the activity due to the radioactive decay of the carbon- in a tiny samp

EleoNora [17]

The question is incomplete. The complete question is:

The half-life for the decay of carbon-14 is 5.73x10^3 years. Suppose the activity due to the radioactive decay of the carbon-14 in a tiny sample of an artifact made of woodfrom an archeological dig is measured to be 2.8x10^3 Bq. The activity in a similiar-sized sample of fresh wood is measured to be 3.0x10^3 Bq. Calculate the age of the artifact. Round your answer to 2 significant digits.

Answer:

570 years

Explanation:

The activity of the fresh sample is taken as the initial activity of the wood sample while the activity measured at a time t is the present activity of the wood artifact. The time taken for the wood to attain its current activity can be calculated from the formula shown in the image attached. The activity at a time t must always be less than the activity of a fresh wood sample. Detailed solution is found in the image attached.

6 0

3 years ago

jane starts to blink her eyes when her brother shines a flashlight at her. why does jane start blinking her eyes

Ivanshal [37]

There is too much light entering her eyes.

3 0

3 years ago

Equation balancing

meriva

Answer:

For a: The balanced equation is $2S(s)+3O_2(g)\rightarrow 2SO_3(g)$

For c: The balanced equation is $2NaOH(s)+H_2SO_4(aq)\rightarrow Na_2SO_4(aq)+2H_2O(l)$

Explanation:

A balanced chemical equation is one where all the individual atoms are equal on both sides of the reaction. It follows the law of conservation of mass.

For (a):

The given unbalanced equation follows:

$S(s)+O_2(g)\rightarrow SO_3(g)$

To balance the equation, we must balance the atoms by adding 2 infront of both $S(s)$ and $SO_3$ and 3 in front of $O_2$

For the balanced chemical equation:

$2S(s)+3O_2(g)\rightarrow 2SO_3(g)$

For (b):

The given balanced equation follows:

$2Al(s)+3Cl_2(g)\rightarrow 2AlCl_3(s)$

The given equation is already balanced.

For (c):

The given unbalanced equation follows:

$2NaOH(s)+H_2SO_4(aq)\rightarrow Na_2SO_4(aq)+H_2O(l)$

To balance the equation, we must balance the atoms by adding 2 infront of $H_2O(l)$

For the balanced chemical equation:

$2NaOH(s)+H_2SO_4(aq)\rightarrow Na_2SO_4(aq)+2H_2O(l)$

For (d):

The given balanced equation follows:

$C_3H_8(g)+5O_2(g)\rightarrow 3CO_2(g)+4H_2O(g)$

The given equation is already balanced.

4 0

3 years ago

Which of the following acids is the WEAKEST? The acid is followed by its Ka value.HF, 3.5 × 10^-4HNO2, 4.6 × 10^-4HCN, 4.9 × 10^

Mila [183]

Answer:

HCN

Explanation:

There are several factors that can tell us when an acid is stronger than another, which are the following:

1. The Polarity of the X - H Bond

2. Size of the X atom.

3. Charge on the acid.

4. Oxidation state of the central atom

5. Values of Ka and pKa.

From all of this factors, we can see that the exercise is already giving us values of Ka, and also we have different types of acid, not only with the form H - X

So, we will base the force of an acid by it's pKa value.

The pKa value which is calculated with the expression:

pKa = -logKa

pKa is a value that indicates how strong is the acid you are working with. This value can vary depending on factors such the charge of the acid. I f this charge can be easily distributed in resonance structures, the compound is more acidic, and therefore the pKa value is lower.

The lower the pKa, the more acidic the compound is.

So calculating the pKa on every structure we have:

HF: pKa = -log(3.5x10^-4) = 3.46

HNO2: pKa = -log(4.6x10^-4) = 3.34

HCN: pKa = -log(4.9x10^-10) = 9.31

HCOOH: pKa = -log(1.8x10^-4) = 3.74

HClO2: -log(1.1x10^-2) = 1.96

So according to all this values, we can conclude that the weakest acid is the HCN

4 0

3 years ago

Mercury thermometers work because mercury ____ when it is warmed