All categories

3 years ago

11. What are transition metals?

Chemistry

1 answer:

kolezko [41]3 years ago

8 0

Answer:

Elements that fall between those on the left and right sides of the periodic table

Explanation:

Transition metals:

These are present at the center of periodic table.

These are d-block elements.

They include the elements of group 3 to 12 in periodic table.

They have large charge to radius ratio.

They mostly form paramagnetic compounds.

They shoes more than one oxidation state.

They form colored compounds.

They all have high melting and boiling point.

They have high densities.

They form stable complexes.

The elements of f-block are also transition but they are called inner transition.These are consist of two series lanthanide and actinides.

You might be interested in

An atom with 13 protons and an unknown number of neutrons is called____?

MaRussiya [10]

Aluminum contains 13 protons

4 0

3 years ago

Read 2 more answers

How much heat in joules is required to heat a 43g sample of aluminum from an initial temperature of 72˚F to a final temperature

Stels [109]

The first step to answering this item is to convert the given temperatures in °F to °C through the equation,

°C = (°F - 32)(5/9)

initial temperature: 72°F

  °C = (72 - 32)(5/9) = 22.22°C

final temperature: 145°F

  °C = (145 - 32)(5/9) = 62.78°C

Substituting to the equation,

H = mcpdT

H = (43 g)(0.903 J/g°C)(62.78 - 22.22)

H = 1574.82 J

<em>Answer: 1574.82 J</em>

3 0

3 years ago

What is the percent by mass of a solution containing 4. 0g of solute in 100g of water? (Percent by mass formula: (mass of solute

Hoochie [10]

B
mass of solute - 4.0 g
mass of solution - 100g + 4.0g = 104g
4/104 = 0.03846
0.03846 • 100 = 3.8%

5 0

2 years ago

The thallium (present as Tl2SO4) in a 9.486-g pesticide sample was precipitated as thallium(I) iodide. Calculate the mass percen

tino4ka555 [31]

Answer: The mass percentage of $Tl_2SO_4$ is 5.86%

Explanation:

To calculate the mass percentage of $Tl_2SO_4$ in the sample it is necessary to know the mass of the solute ( $Tl_2SO_4$ in this case), and the mass of the solution (pesticide sample, whose mass is explicit in the letter of the problem).

To calculate the mass of the solute, we must take the mass of the $TlI$ precipitate. We can establish a relation between the mass of $TlI$ and $Tl_2SO_4$ using the stoichiometry of the compounds:

$moles\ of\ TlI = \frac{0.1824 g}{331.27\frac{g}{mol} } = 5.51*10^{-4}\ mol.$

Since for every mole of Tl in $TlI$ there are two moles of Tl in $Tl_2SO_4$ , we have:

$moles\ of\ Tl_2SO_4 = 2 * moles\ of\ TlI = 1,102*10^{-3}\ mol$

Using the molar mass of $Tl_2SO_4$ we have:

$mass\ of\ Tl_2SO_4 = 1,102*10^{-3}\ mol * 504.83\ \frac{g}{mol}= 0.56\ g$

Finally, we can use the mass percentage formula:

$mass\ percentage = (\frac{solute\ mass}{solution\ mass} )*100 = (\frac{mass\ of\ Tl_2SO_4}{pesticide\ sample\ mass})*100 = (\frac{0.56g}{9.486g})*100 = 5.86\%$

6 0

2 years ago

Question 4

nata0808 [166]

Answer:

A. She can run the same distance in a shorter amount of time.

Explanation:

Speed can be computed with the formula:

$v = \dfrac{d}{t}$

Where:

v = speed

d = distance

t = time

So if you look at the formula, distance there tells you how far an object has traveled, and the time tells us how long it took to cover that distance. As you can see, speed and time are <u>inversely proportional. </u>This means that as one goes up, the other goes down. So if we reduce time travelling a certain distance, the speed increases.

3 0

3 years ago