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Nadya [2.5K]
3 years ago
8

Round off the following number to 3 digits 34,560​

Chemistry
1 answer:
Vikki [24]3 years ago
6 0

Answer:

3.46x10⁴

Explanation:

Hello,

In this case, we can see that the number 34,560 has five significant figures, it means that if we want to write it with three, we must take the 3, 4 and 5 only. Nevertheless, since the 6 after the five is greater than 5, we can round such five to 6, so we obtain:

346

However, the decimal places cannot get lost, therefore, we move the given thousand  to the three, so the number turns out:

3.46x10⁴

Best regards.

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Selah is making a mobile of an atom of beryllium to hang from the ceiling in her science class. She uses a clear plastic bag for
mel-nik [20]

Answer:

See explanation

Explanation:

The question is incomplete because the images of the models are absent. However, i will try to give you a general description of what the correct answer should be.

Beryllium is a member of group 2 in the periodic table. Beryllium has an atomic number of 4. This implies that it has four protons in its nucleus and four electrons in its shells. In a neutral atom, the number of electrons on the shells is equal to the number of protons in the nucleus.

The electronic configuration of Beryllium is 1s2 2s2. This implies that it should have two shells each containing only two electrons each.

Since we are using white foam balls for protons and black foam balls for neutrons, the clear plastic will contain four white foam balls and five  black foam balls since the mass number of beryllium is 9 and number of neutrons = mass number - number of protons.

Four blue foam balls hanging from strings will represent the electrons around the nucleus.

Any model that corresponds to the description above is the correct answer.

7 0
3 years ago
Identify the following as a compound or a mixture: quartz (SiO2)
Bumek [7]
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3 0
3 years ago
Chlorine can be prepared in the laboratory by the reaction of manganese dioxide with hydrochloric acid, HCl ( aq ) , as describe
Nataly [62]

Answer:

0.9483 grams of manganese dioxide should be added to excess HCl.

Explanation:

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Moles of chlorine gas = n

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PV = nRT

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8 0
3 years ago
A solution containing 0.050 g of an unknown nonelectrolyte in 2.50 g of cyclohexane (Kf = 20.4 oC/m &amp; F.P. 6.6 oC) was found
ANEK [815]

Answer:

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Therefore 1 Mole weighs (0.05 g)/(1.96 × 10⁻⁵ moles) = 255g/mole

7 0
3 years ago
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