Please help :( this is for science.

3. Which of the following is not true for atoms? (4 points) They combine to form elements and molecules. They contain negatively

Taya2010 [7]

<h3><u>Answer;</u></h3>

They are made up of elements.

<h3><u>Explanation;</u></h3>

An atom is the smallest particle of matter that still retains the property of the element.
Two or more atoms combine to form elements or compounds. Elements are formed by two or more similar atoms, while compounds are formed by two or more different elements.
Atoms are made up of subatomic particles; protons, electrons and neutrons. Electrons are negatively charged, protons are positively charged while neutrons have no charge.

7 0

3 years ago

Como se representan los elementos en la tabla¿?

Shalnov [3]

Answer:

Na sodiops los elementos químicos se representan como el átomo, el núcleo, donde se necuentran los protones y neutrones van dentro, los electrones afuera, girando de forma elíptica alrededor del núcleo. ... por ejemplo el oxígeno numero atómico 8, tiene 8 protones y 8 electrones. el número de neutrones es diferente.

Explanation:

4 0

3 years ago

Calculate the mass of magnesium carbonate ( MgCO3), in grams, required to produce 110.0 g of carbon dioxide using the following

bearhunter [10]

Answer:

$210.7~g~MgCO_3$

Explanation:

We have to start with the <u>reaction</u>:

$MgCO_3~->~MgO~+~CO_2$

We have the same amount of atoms on both sides, so, we can continue. The next step is to find the <u>number of moles</u> that we have in the 110.0 g of carbon dioxide, to this, we have to know the <u>atomic mass of each atom</u>:

C: 12 g/mol

O: 16 g/mol

Mg: 23.3 g/mol

If we take into account the number of atoms in the formula, we can calculate the <u>molar mass</u> of carbon dioxide:

$(12*1)+(16*2)=44~g/mol$

In other words: $1~mol~CO_2=~44~g~CO_2$ . With this in mind, we can calculate the moles:

$110~g~CO_2\frac{1~mol~CO_2}{44~g~CO_2}=25~mol~CO_2$

Now, the <u>molar ratio</u> between carbon dioxide and magnesium carbonate is 1:1, so:

$2.5~mol~CO_2=2.5~mol~MgCO_3$

With the molar mass of $MgCO_3$ ( $(23.3*1)+(12*1)+(16*3)=84.3~g/mol$ . With this in mind, we can calculate the <u>grams of magnesium carbonate</u>:

$2.5~mol~MgCO_3\frac{84.3~g~MgCO_3}{1~mol~MgCO_3}=210.7~g~MgCO_3$

I hope it helps!

8 0

3 years ago

For the balanced equation shown below, what would be the limiting reagent if 93.9grams

svlad2 [7]

Answer: A. C2H3F

Explanation:

5 0

3 years ago

Be sure to answer all parts. Part 1 out of 2 how many electrophilic centers are present in acetyl chloride (ch3cocl)?

natima [27]

<h3>Answer:</h3>

There is One electrophilic center in acetyl chloride.

<h3>Explanation:</h3>

Electrophile is defined as any specie which is electron deficient and is in need of electrons to complete its electron density or octet. The main two types of electrophiles are those species which either contain positive charge (i.e. NO₂⁺, Cl⁺, Br⁺ e.t.c) or partial positive charge like that contained by the sp² hybridized carbon of acetyl chloride shown below in attached picture.

In acetyl chloride the partial positive charge on sp² hybridized carbon is generated due to its direct bonding to highly electronegative elements *with partial negative charge) like oxygen and chlorine, which tend to pull the electron density from carbon atom making it electron deficient and a good electrophile for incoming nucleophile as a center of attack.

7 0

3 years ago