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3 years ago

HELP TIMED !!!!

Chemistry

2 answers:

Troyanec [42]3 years ago

6 0

Hello there what is the question?

kipiarov [429]3 years ago

3 0

Answer:

Helium is one of the lightest gas that is found to be stored in the interior of the earth's crust. This helium gas is formed from the constant radioactive decay process. During the time of radioactive decay, the radioactive elements decays and give rise to the formation of alpha particles, which are positively charged. When a pair of electrons are combined with these alpha particles then it produces helium atom.

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PLEASE HELP ME ASAP PLEASE!

liberstina [14]

Answer:

the equation is balanced because there are 8 atoms of carbon, 26 atoms of oxygen, and 20 atoms of hydrogen. on each side of the equation.

PLEASE MARK BRAINLIEST

8 0

2 years ago

The mole fraction of a non-electrolyte (MM 40.0 g/mol) in a saturated aqueous solution is 0.310. What is the molality of the sol

jeka57 [31]

<u>Answer:</u> The molality of non-electrolyte is 24.69 m

<u>Explanation:</u>

We are given:

Mole fraction of saturated aqueous solution = 0.310

This means that 0.310 moles of non-electrolyte is present.

Moles of water (solvent) = 1 - 0.310 = 0.690 moles

To calculate the mass from given number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Moles of water = 0.690 moles

Molar mass of water = 18 g/mol

Putting values in above equation, we get:

$0.690mol=\frac{\text{Mass of water}}{18g/mol}\\\\\text{Mass of water}=(0.690mol\times 18g/mol)=12.42g$

To calculate the molality of solution, we use the equation:

$\text{Molality}=\frac{n_{solute}\times 1000}{W_{solvent}\text{ (in grams)}}$

Where,

$n_{solute}$ = Moles of solute (non-electrolyte) = 0.310 moles

$W_{solvent}$ = Mass of solvent (water) = 12.42 g

Putting values in above equation, we get:

$\text{Molality of non-electrolyte}=\frac{0.310\times 1000}{12.42}\\\\\text{Molality of non-electrolyte}=24.96m$

Hence, the molality of non-electrolyte is 24.69 m

4 0

3 years ago

Which one of the following is most likely to be an ionic compound? SO2

liubo4ka [24]

Answer:

Ionic compounds generally form between elements that are metals and elements that are nonmetals. For example, the metal calcium (Ca) and the nonmetal chlorine (Cl) form the ionic compound calcium chloride (CaCl2). In this compound, there are two negative chloride ions for each positive calcium ion

3 0

3 years ago

An element that appears in the lower left corner of the periodic table is

Xelga [282]

This problem is honestly, very easy. Just grab a periodic table and find the element in Group 1 and Period 7. But first, let's discuss how the elements are arranged systematically in a periodic table. There are a lot of scientists who contributed to it, but the most famous one is Dimitri Mendeleev. He arranged the elements according to their atomic number. The elements starts from 1 which is Hydrogen up to the heaviest known elements which is Oganesson with an atomic number of 118. As you can observe, there is a gap between groups 3 and 4. This is done so that the periodic table does not take too much space horizontally. Thus, they are just placed at the bottom. These elements are called lanthanides (upper row) and actinides (lower row). The rows in the periodic table are called groups, and the columns are called periods.

Now, the element at the lower left corner (Group 1, Period 7) is Francium, abbreviated as Fr. It has an atomic number of 87. Some elements are actually synthesized, but Francium is a naturally occurring radioactive element. It was discovered by Marguerite Perey in France.

6 0

3 years ago

Where does transcription happen? why is it only in this location?

jeka57 [31]

Nucleus because that’s where dna is

4 0

3 years ago