Boron (B) has two Isotopes, boron-10 and boron-11. The atomic weight of boron is the

Most atoms follow the octet rule meaning they need ------ electrons to fill their valence shells. One important exception is H w

Serggg [28]

Answer:

The octet rule means that atoms need a total of 8 valence electrons to fill their valence shell. Hydrogen only needs two to fill its valence shell.

Explanation:

All atoms except for hydrogen can hold a total of 8 valence electrons in their outer energy levels (2 in the s level, 6 in the p level). Hydrogen only has two electrons total, so it does not require more than the s level and two electrons to have a full valence.

5 0

3 years ago

Read 2 more answers

Which of the following describe chemical properties? check all that apply

yanalaym [24]

I think the correct answers from the choices listed above are the first and the last options. It would be helium that is the lightest monoatomic element and that an<span>tacid tablets neutralize stomach. Hope this answers the question. Have a nice day.</span>

6 0

4 years ago

Calculate the volume occupied by 32.0 g of O2 gas, the pressure of the O2 gas is 78.5 kPa at 25°C.

Oksi-84 [34.3K]

Answer: 31.5L

Explanation:

6 0

3 years ago

Calculate the number of atoms in 2.5 moles of Si.

Ede4ka [16]

Answer:

$\boxed {\boxed {\sf About \ 1.5 * 10^{24} \ atoms \ Si}}$

Explanation:

When converting from moles to atoms, we must use Avogadro's number. This number tells us there are 6.022 * 10²³ atoms in 1 mole. We can multiply this number by the number of moles.

First, we must set up Avogadro's number as a ratio.

$\frac {6.022 \ * 10^{23} \ atoms \ Si }{1 \ mol \ Si}}$

Next, multiply the number of moles by the ratio.

$2.5 \ mol \ Si *\frac {6.022 \ * 10^{23} \ atoms \ Si }{1 \ mol \ Si}}$

When we multiply, the moles of silicon will cancel.

$2.5 * \frac {6.022 \ * 10^{23} \ atoms \ Si }{1}}$

Since the denominator of the fraction is 1, we can cancel it out too.

$2.5 * {6.022 \ * 10^{23} \ atoms \ Si }$

$1.5055 * 10^{24} \ atoms \ Si$

The original measurement (2.5 moles) has 2 significant figures (2 and 5). Therefore we must round to 2 sig figs. For this question, 2 sig figs is the tenth place.

The 0 in the hundredth place tells us to leave the 5 in the tenth place.

$1.5 * 10^{24} \ atoms \ Si$

There are about <u>1.5 * 10²⁴ atoms of silicon.</u>

7 0

3 years ago

If potassium (K) and chlorine (CI) form an ionic bond, K will become a cation and CI

Tresset [83]

Answer:

True

Explanation:

It is true as metals form a positive ion when they take part in a chemical reaction. Nonmetals form an anion when bonding.

:)

3 0

3 years ago