What is the isotopic symbols for Beryllium atom that contains 9 nucleon?

A lake in California contains about 8,500,000,000,000 gallons of water. How can this

aniked [119]

Answer:

8.5 * 10^11

Explanation:

8 0

2 years ago

Rank the following atoms in order of decreasing first ionization energies (i.e., highest to lowest): Li, Be, Ba, F.

Minchanka [31]

Answer:

The order is:

F >Be >Li >Ba

Explanation:

Electrons are held in atoms by their attraction to the nucleus which means that to remove an electron from the atom energy is needed.

The ionization energy is the minimum energy necessary to remove an electron from an atom in the gas phase and ground state, the electron removed being the outermost, that is, the furthest from the nucleus. The further away the electron is from the nucleus, the easier it is to remove it, that is, the less energy is needed.

By increasing the atomic number of the elements of the same group, the nuclear attraction on the outermost electron decreases, since the atomic radius increases. Then the ionization energy decreases. In other words, in a group it decreases from top to bottom because the size of the atom increases and it is easier to remove an external electron.

By increasing the atomic number of the elements of the same period, the nuclear attraction on the outermost electron increases, since the atomic radius decreases. Therefore, in a period, as the atomic number increases, the ionization energy increases. In summary, in a period it increases from left to right as the effective nuclear charge increases and it increases thanks to the decrease in the size of the atom.

Taking these considerations into account, the order is:

F >Be >Li >Ba

5 0

2 years ago

8. A sample of potassium chlorate (KCIO,) was heated in a test tube and decomposed 2KC?(s) 302 (g) + 2KCIO, (s) The oxygen was c

dangina [55]

Answer:

Partial pressure of $O_{2}$ in the gas was 733 torr and mass of $KClO_{3}$ in the sample was 2.12 g.

Explanation:

a) Total pressure of gas = (partial pressure of water vapour)+(partial pressure of $O_{2}$ )

Here partial pressure of water vapour is 21 torr and total pressure of gas is 754 torr.

So, partial pressure of $O_{2}$ = (total pressure of gas)-(partial pressure of water vapour) = (754 torr) - (21 torr) = 733 torr

b) Lets assume that $O_{2}$ behaves ideally. Hence-

PV=nRT

where P is pressure of $O_{2}$ , V is volume of $O_{2}$ , n is number of moles of $O_{2}$ , R is gas constant and T is temperature in kelvin

here P = 733 torr = $(733\times 0.001316)atm$ = 0.9646 atm

V = 0.65 L, R = 0.082 L.atm/(mol.K), T=(273+22)K = 295 K

So, $n=\frac{PV}{RT}$

= $\frac{(0.9646 atm)\times (0.65 L)}{(0.082 L.atm/(mol.K))\times (295 K)}$

= 0.0259 moles

As 3 moles of $O_{2}$ are produced from 2 moles of $KClO_{3}$ therefore 0.0259 moles of $O_{2}$ are produced from $(\frac{2\times 0.0259}{3})$ moles or 0.0173 moles of $KClO_{3}$ .

Molar mass of $KClO_{3}$ = 122.55 g

So mass of $KClO_{3}$ in sample = $(0.0173\times 122.55)g$

= 2.12 g

7 0

3 years ago

10 uses of water good answer

Vikentia [17]

Answer:

For drinking.

For cleaning dishes.

For cooking.

for watering plants.

for washing clothes.

for bathing.

for generation of hydroelectricity.

for washing car.

making our dog bath

it helps in maintaining osmotic rate in humans

Explanation:

Hope this helps u

Crown me as brainliest

5 0

2 years ago

Read 2 more answers

It is easier to determine the electron configurations for the p-block elements in periods 1, 2, and 3 than to determine the elec

andreyandreev [35.5K]

Answer:

See Explanation

Explanation:

Because you have to get through the d-block electron configurations for the rest of the p-block elements which is a hassle to do. You need to know how to account for electron stability, from which subshell to remove electrons, etc. because it is all weird for d-block.

8 0

1 year ago