How many protons does silicon have?

28
2
14
28.08

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Answer:

tysm

tysm

tysm dear

Answer:It’s cyclone movement

Explanation:

The atomic radius of Argon is smaller than the atomic radius of sodium because the effective nuclear charge increases as we move left to right in a period.

The atomic radius can be described as the shortest distance between the center of the nucleus of the atom and the outermost shell of the atom. An atomic radius can also be defined as half the distance between two atoms of the same element bonded together.

In general, the atomic radius of an atom reduces as we move from left to right in a period on the periodic table because while moving from left to right in a period, there is an increase in the effective nuclear charge. In periods, the valence electrons enter in the same outermost shell.

The atomic radius of atom increases when we move down a group because of the addition of a new principle shell.

Sodium is present at beginning of the third period and the Argon is present at the end of the same period. Therefore, Argon experiences a more effective nuclear charge than sodium so it has a smaller atomic radius.

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Answer:

D

Explanation:

Its D

Answer:

Its d for edge

Explanation:

Answer:

b or d

Explanation:

Answer:

The answer is B (it's reactivity)

Answer:

lll and ll

Explanation:

Answer:1, 2, and 4

Explanation:

covalent bonds are not ionic.  the elements SHARE electrons

Which of the following are properties of compounds formed by covalent bonding (Select all that apply)  

1. When you dissolve an covalent compound in water, the solution does not conduct electricity.

2. Covalent compounds often have lower melting points than ionic compounds.

3. When you dissolve an covalent compound in water, the solution conducts electricity.

4. Covalent compounds form when combining two or more nonmetal atoms.

5. Covalent compounds form when combining a two metal atoms.

6. Covalent compounds form when combining a metal atom with a nonmetal atom.

The properties of covalent compounds are option 2, 3 and 4. Covalent bonds are weaker than ionic bonds.

Covalent bonds are formed by sharing electrons between two atoms. Non metals with comparable electronegativities forms covalent bonds. They are weaker than ionic bond. Thus have lower melting point.

Melting point depends on the bond strength that's why covalent compounds have lower melting point compared with ionic bonds.

Polar covalent bonds can conduct electricity when dissolved in water because of the presence of free electrons. Thus option 3 is correct.

Hence, the properties in option 2, 3 and 4 are correct for covalent compounds.

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Answer:

a) II and III

is the correct

Answer:

Blue!!

I think it is blue!

is it blue cuz i think its blue

Answer:

d

Explanation:

Answer:

Explanation:

The potential energy of a body can be found by using the formula

PE = mgh

where

m is the mass

h is the height

g is the acceleration due to gravity which is 9.8 m/s²

From the question we have

PE = 3 × 9.8 × 12.5 = 367.5

We have the final answer as

Hope this helps you

2. You work for an environmental company as an environmental toxicologist and have been hired to determine the contaminant present in a local resident’s pool. Create a flow chart outlining how you would detect the possible presence of Fe2+ and/or Sr2+

Answer:

All of them are equal cause they both have the same sign

Explanation:

Answer:

46.2 amu

Explanation:

The average atomic mass of an element can be determined using the percentage abundance and mass of its isotopes. The average atomic mass of the hypothetical element Jovian is 46.2 amu.

Most of the elements have two or more isotopes in nature with different percentage abundance and mass. The average atomic mass of the element is then calculated using the formula written below:

Average atomic mass = % abundance /100 × mass of isotope 1  +  % abundance /100 × mass of isotope 2 + .....

Given the mass % abundance of Jovian -44 = 22.4 %

Jovian- 46 = 44 %

Jovian -48 = (100 - (44 + 22.4)) = 33.6 %

Average atomic mass of Jovian  =  ( 22.4 /100 × 44 ) +  ( 44 /100 × 46) +  ( 33.6  /100 × 48 ) = 46.2 amu

Therefore, the average atomic mass of the hypothetical element is 46.2 amu.

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Answer:

the "goldilocks zone" is the habitable zone around a star where it's not too hot and not too cold, so liquid water and life can exist on the planets in this zone.

Explanation:

The distance Earth orbits the Sun is just right for water to remain a liquid and for life to not be frozen or fried. This distance from the Sun is called the habitable zone, or the Goldilocks zone.

Answer:

About 67 grams or 67.39 grams

Explanation:

First you would have to remember a few things:

 enthalpy to melt ice is called enthalpy of fusion.  this value is 6.02kJ/mol

  of ice  

 it takes 4.18 joules to raise 1 gram of liquid water 1 degree C

 water boils at 100 degrees C and water melts above 0 degrees C

 1 kilojoules is 1000 joules

  water's enthalpy of vaporization (steam) is 40.68 kJ/mol

  a mole of water is 18.02 grams

  we also have to assume the ice is at 0 degrees C

Step 1

Now start with your ice.  The enthalpy of fusion for ice is calculated with this formula:

q = n x ΔH    q= energy, n = moles of water, ΔH=enthalpy of fusion

Calculate how many moles of ice you have:

150g x (1 mol / 18.02 g) = 8.32 moles

Put that into the equation:

q = 8.32 mol x 6.02 = 50.09 kJ of energy to melt 150g of ice

Step 2

To raise 1 gram of water to the boiling point, it would take 4.18 joules times 100 (degrees C)  or 418 joules.

So if it takes 418 joules for just 1 gram of water, it would take 150 times that amount to raise 150g to 100 degrees C.  418 x 150 = 62,700 joules or 62.7 kilojoules.

So far you have already used 50.09 kJ to melt the ice and another 62.7 kJ to bring the water to boiling.  That's a total of 112.79 kJ.

Step 3

The final step is to see how much energy is left to vaporize the water.

Subtract the energy you used so far from what you were told you have.

265 kJ - 112.79 kJ = 152.21 kJ

Again q = mol x ΔH (vaporization)

You know you only have 152.21 kJ left so find out how many moles that will vaporize.

152.21 kJ = mol x 40.68  or   mol = 152.21 / 40.68  = 3.74 moles

This tells you that you have vaporized 3.74 moles with the energy you have left.

Convert that back to grams.

3.74 mol   x  ( 18.02 g / 1 mol ) = 67.39 grams

1bonding and 3non-bonding

(Refer to the attachment for structure

Answer:

it is placed over a bunsen burner to heat up and remove all bacteria

Explanation:

Answer:

Freezing and condensation

Explanation:

Because they are exothermic, they release energy

The alkyl halide that forms the alkene shown as the only  product in an elimination reaction is bromomethyl cyclohexane.

An elimination reaction is a reaction in which two atoms are removed to create a double bond. Elimination reaction is a type of reaction that is common to alkyl halides.

In this reaction, a hydrogen atom and a halogen atom are both removed to yield a double bond. The structure of the product depends on the structure of the reactant alkyl halide.

Bromomethylcyclohexane shown in the image attached yields the alkene product in the image attached as the only product when it undergoes elimination reaction.

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Answer:

0.690 liters is the volume of hydrogen gas produced if 2.00 grams of zinc is used with an excess of hydrochloric acid.

Explanation:

Zn(s)+2HCl(aq)\rightarrow ZnCl_2(aq)+H_2(g)Zn(s)+2HCl(aq)→ZnCl2(aq)+H2(g)

Mole so zinc = \frac{2.00}{65 g/mol}=0.03077 mol65g/mol2.00=0.03077mol

According to reaction, 1 mole of zinc gives 1 mole of hydrogen gas.

Then 0.03077  mole of zinc will give :

\frac{1}{1}\times 0.03077 mol=0.03077 mol11×0.03077mol=0.03077mol of hydrogen gas

Pressure of hydrogen gas ,P= 1 atm

Temperature  of of hydrogen gas ,T= 273.15 K

Volume of hydrogen gas = V = ?

Moles of hydrogen gas = 0.03077 mol

PV = nRT (Ideal gas equation )

V=\frac{nRT}{P}=\frac{0.03077 mol\times 0.0821 atm L/mol K\times 273.15 K}{1 atm}V=PnRT=1atm0.03077mol×0.0821atmL/molK×273.15K

V = 0.690 L

Answer:

Atoms gain valence electrons to form anions.

Explanation:

Answer:

1. Decomposition of stone due to acid rain.

3. The pink color of a rose.

Explanation:

Chemical changes always end up with new products in an equation, or it has always something to do with chemicals. Physical changes on the other hand, do not result in new products and it just changes the physical properties and physical state of matter of the object.

Sodium (Na) and Argon (Ar) on the periodic table does not have similar properties.

PERIODIC TABLE:

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Answer:

H+ (hydrogen) ions

Explanation:

Answer:

H+ (hydrogen) ions

Explanation: