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3 years ago

Who are the scientists that contributed in arranging of the periodic table?

1 answer:

7 0

In 1869 Russian chemist DIMITRI MENDELEEV started the development of the periodic table,arranging chemical elements by atomic mass. He predicted the discovery of other elements and left spaces open in his periodic table for them. HOPE THIS HELPSS HAVE A GREAT DAY <333

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Potassium carbonate, K 2CO 3, sodium iodide, NaI, potassium bromide, KBr, methanol, CH 3OH, and ammonium chloride, NH 4Cl, are s

slava [35]

Answer:

Potassium carbonate (K₂CO₃)

Explanation:

The compounds dissociate into ions in water, as follows:

K₂CO₃ → 2 K⁺ + CO₃⁻ ⇒ 3 dissolved particles per mole

NaI → Na⁺ + I⁻ ⇒ 2 dissolved particles per mole

KBr → K⁺ + Br⁻ ⇒ 2 dissolved particles per mole

CH₃OH → CH₃O⁻ + H⁺ ⇒ 2 dissolved particles per mole

NH₄Cl → NH₄⁺ + Cl⁻ ⇒ 2 dissolved particles per mole

Therefore, the largest number of dissolved particles per mole of dissolved solute is produced by potassium carbonate (K₂CO₃).

3 0

3 years ago

3 waves are shown with a line through their center. The bottom of the first wave is labeled C. A bracket labeled D connects the

Likurg_2 [28]

Answer:Label the parts of this wave.

✔ crest

✔ amplitude

✔ trough

✔ wavelength

Explanation:

8 0

3 years ago

Read 2 more answers

A flask with a volume of 3.16 l contains 9.33 grams of an unknown gas at 32.0°c and 1.00 atm. What is the molar mass of the gas?

Inessa05 [86]

Answer:

73.88 g/mol

Explanation:

For this question we have to keep in mind that the unknown substance is a gas, therefore we can use the ideal gas law:

$PV=nRT$

In this case we will have:

P= 1 atm

V= 3.16 L

T = 32 ªC = 305.15 ºK

R= 0.082 $\frac{atm*L}{mol*K}$

n= ?

So, we can solve for "n" (moles):

$1~atm*3.16~L~=~n*0.082~\frac{atm*L}{mol*K}*305.15~K$

$n=\frac{1~atm*3.16~L~}{0.082~\frac{atm*L}{mol*K}*305.15~K}$

$n=0.126~mol$

Now, we have to remember that the molar mass value has "g/mol" units. We already have the grams (9.33 g), so we have to divide by the moles:

$molar~mass=\frac{9.33~grams}{0.126~mol}$

$molar~mass=73.88\frac{grams}{mol}$

7 0

3 years ago

Which organisms in this food web are carnivores? Select the two correct

LUCKY_DIMON [66]

The two correct options are Poison dart frog and Boa constrictor. Both these organisms are pure carnivores which are also known as pure meat eaters in the food web. Carnivores are organisms in the food chain that only meat-eaters and never take any type of vegetation in their diet.

Explanation:

A Poison dart frog purely survives on meat (meat- eater).
Long sticky tongues are used to catch their prey such as ants, flies, insects.
Since they produce high toxin levels, it has very few predators in the wild.
Boa constrictor is also an organism that eats only meat.
While they are young they eat prey like rats, squirrels and mice.
The type of attack used by a boa constrictor is an ambush attack type. It attacks its preys using the surprise factor.

6 0

4 years ago

I need the answer so much

Mariulka [41]

I don't know sorry just google it

4 0

3 years ago