What is a group of electrons orbiting at roughly the same distance from the nucleus

The dessert can be harsh environment with extreme heat during the day and cold during the night also there is very little rainfa

Sphinxa [80]

Answer:

True

Explanation:

The desert refers to a region of arid land which is characterized by extreme temperatures, extreme dryness, low amount of precipitation and generally harsh living conditions. Because of these harsh conditions, they have been tagged with various names ranging from 'Death Valley' to 'the place from where there is no return' etc.

Every desert is made up of 2 components: the <u>biotic (living) component</u> and the <u>abiotic (non-living) component</u>. The biotic (living) component consists of the plants and animals that have adapted to these harsh living conditions e.g. Cactus or Cacti, Holly plants, Camels, Lizards, Snakes etc. The abiotic (non-living) component consists of climate (subtropical deserts which are extremely cold or temperate deserts which are extremely hot), location, precipitation/rainfall

8 0

2 years ago

Combination (Synthesis) Reactions<br> pls help!

Ratling [72]

Answer: 1. CaO + H2O => Ca(OH)2

2. P4 + 5O2 => 2P2O5

3. 2 Ca + O2 => 2 CaO

4. 8 Cu + S8 => 8 CuS

5. CaO + H2O => Ca(OH)2

6. S8 + 8 O2 => 8 SO2

7. 3 H2 + N2 => 2 NH3

8. H2 + Cl2 =>2 HCl

9. 16 Ag + S8 => 8 Ag2S

10. Cr + O2 => 2Cr2O3

11. 2Al + 3Br2 => 2AlBr3

12. 2Na + I2 => 2NaI

13. 2H2 + O2 =>2 H2O

14. 4 Al + 3O2 => 2 Al2O3

Explanation:

4 0

2 years ago

H2CO3(aq) + H200 H30 (aq) + HCO3 (aq).

timofeeve [1]

Answer:

$K_a=\frac{[H_3O^+][HCO_3^-]}{[H_2CO_3]}$

Explanation:

Several rules should be followed to write any equilibrium expression properly. In the context of this problem, we're dealing with an aqueous equilibrium:

an equilibrium constant is, first of all, a fraction;
in the numerator of the fraction, we have a product of the concentrations of our products (right-hand side of the equation);
in the denominator of the fraction, we have a product of the concentrations of our reactants (left-hand side o the equation);
each concentration should be raised to the power of the coefficient in the balanced chemical equation;
only aqueous species and gases are included in the equilibrium constant, solids and liquids are omitted.

Following the guidelines, we will omit liquid water and we will include all the other species in the constant. Each coefficient in the balanced equation is '1', so no powers required. Multiply the concentrations of the two products and divide by the concentration of carbonic acid:

$K_a=\frac{[H_3O^+][HCO_3^-]}{[H_2CO_3]}$

4 0

3 years ago

What is the gcf of 16 and 72? <br> a. 2 <br> b. 4 <br> c. 16 <br> d. 8

nadya68 [22]

Your answer is D. 8

16 = 2^4
72 = 2^3*3^2

So you'll choose 2^3 = 8

7 0

3 years ago

Read 2 more answers

6. What is the oxidation number for the atom indicated in the following compounds.

Hatshy [7]

Answer:

a. +6;

b. +5;

c. +3.

Explanation:

Start with elements with well-known oxidation states.

The oxidation state on oxygen O in compounds is mostly -2. Common exceptions include:

-1 in peroxides and
positive when oxygen bonds to fluorine.

The oxidation state on group 1 metals (Li, Na, K, etc.) in compounds is mostly +1.

The oxidation state on group 2 metals (Be, Mg, Ca, etc.) in compounds is mostly +2.

Barium Ba is a group 2 metal. The oxidation state on Ba in the compound BaSO₄ is expected to be +2.

The oxidation state on hydrogen H in compounds is mostly +1. The oxidation state on H might be negative when it is bonded to metals.

The oxidation state on halogens (F, Cl, Br, etc.) is mostly -1. The oxidation state may vary when the halogen is bonded to oxygen or another halogen element.

Compounds are neutral. The oxidation state on all atoms in a compound shall add up to 0. Both BaSO₄ and HClO₂ are neutral.

Oxidation states:

Ba: +2;
The oxidation state on sulfur S is to be determined;
O: -2.

Let the oxidation state on S be x.

2 + x + 4 × (-2) = 0;

x = 6.

Hence, the oxidation state on S in BaSO₄ is +6.

Oxidation states:

H: +1;
Cl here is bonded to oxygen. The oxidation state on chlorine Cl is to be determined;
O: -2.

Let the oxidation state on Cl be x.

<em>Refer to the equation in BaSO₄ as an example. Try setting up the equation on your own. </em>

x = 3.

Hence, the oxidation state on Cl is +3.

Ions carry charge. Oxidation states on atoms in an ion shall add up to the charge of the ion. The superscript of an ion shows its charge. The superscript 3- in the phosphate ion shows that the ion carries a charge of -3.

Oxidation states:

The oxidation state on P is to be found;
O: -2.

Let the oxidation state on P be x.

x + 4 × (-2) = -3;

x = 5.

Hence, the oxidation state on P is +5.

4 0

2 years ago