All categories

3 years ago

Need Help On This...Thanks

Chemistry

1 answer:

ollegr [7]3 years ago

6 0

13) "..From the ___" My guess would be Sun since it says solar later in the question. Then an example of solar energy would be flashlights, thermostats (etc..)

14) Mechanical

16) Conductors, (Ex. copper, metal)

17) Insulators, most non metallic materials (Ex. cloth, or rubber, plastic)

18) Electrocution

You might be interested in

I am a main group or representative element. I am located in

lesya692 [45]

Answer:

tantalum

i hope this helps<33 :)))))

5 0

2 years ago

What is the molarity of a solution made by mixing 2.80 g of koh with enough water make 750 ml of solution?

Travka [436]

Molarity is expressed as the number of moles of solute per volume of the solution. We calculate as follows:

2.80 g ( 1 mol / 56.11 g ) = 0.05 mol KOH

Molarity = 0.05 mol KOH / 750 mL ( 1 L / 1000 mL )
Molarity = 0.07 M

Hope this answers the question. Have a nice day.

7 0

3 years ago

In 450 BCE, Greek philosopher Democritus first thought of the existence

trasher [3.6K]

Answer:

A. Invisible

Explanation:

3 0

3 years ago

URGENT CHEMISTRY EXPERT!

vovangra [49]

Answer:

Part 1: 7.42 mL; Part 2: 3Cu²⁺(aq) + 2PO₄³⁻(aq) ⟶ 2Cu₃(PO₄)₂(s)

Explanation:

Part 1. Volume of reactant

(a) Balanced chemical equation.

$\rm 2Na_{3}PO_{4} + 3CuCl_{2} \longrightarrow Cu_{3}(PO_{4})_{2} + 6NaCl$

(b) Moles of CuCl₂

$\text{Moles of CuCl}_{2} =\text{ 16.7 mL CuCl}_{2} \times \dfrac{\text{0.200 mmol CCl}_{2}}{\text{1 mL CuCl}_{2}} = \text{3.340 mmol CuCl}_{2}$

(c) Moles of Na₃PO₄

The molar ratio is 2 mmol Na₃PO₄:3 mmol CuCl₂

$\text{Moles of Na$_{3}$PO}_{4} = \text{3.340 mmol CuCl}_{2} \times \dfrac{\text{2 mmol Na$_{3}$PO}_{4}}{\text{3 mmol CuCl}_{2}} =\text{2.227 mmol Na$_{3}$PO}_{4}$

(d) Volume of Na₃PO₄

$V = \text{2.227 mmol Na$_{3}$PO}_{4}\times \dfrac{\text{1 mL Na$_{3}$PO}_{4}}{\text{0.300 mmol Na$_{3}$PO}_{4}} = \text{7.42 mL Na$_{3}$PO}_{4} \\\\\text{The reaction requires $\large \boxed{\textbf{7.42 mL Na$_{3}$PO}_{4}}$}$

Part 2. Net ionic equation

(a) Molecular equation

$\rm 2Na_{3}PO_{4}(\text{aq}) + 3CuCl_{2}(\text{aq}) \longrightarrow Cu_{3}(PO_{4})_{2}(\text{s}) + 6NaCl(\text{aq})$

(b) Ionic equation

You write molecular formulas for the solids, and you write the soluble ionic substances as ions.

According to the solubility rules, metal phosphates are insoluble.

6Na⁺(aq) + 2PO₄³⁻(aq) + 3Cu²⁺(aq) + 6Cl⁻(aq) ⟶ Cu₃(PO₄)₂(s) + 6Na⁺(aq) + 6Cl⁻(aq)

(c) Net ionic equation

To get the net ionic equation, you cancel the ions that appear on each side of the ionic equation.

6Na⁺(aq) + 2PO₄³⁻(aq) + 3Cu²⁺(aq) + 6Cl⁻(aq) ⟶ Cu₃(PO₄)₂(s) + 6Na⁺(aq) + 6Cl⁻(aq)

The net ionic equation is

3Cu²⁺(aq) + 2PO₄³⁻(aq) ⟶ Cu₃(PO₄)₂(s)

7 0

3 years ago

Which statement is true about water molecules?

Arte-miy333 [17]

1. The correct option is A, THE OXYGEN ATOM HAS A NEGATIVE CHARGE. A water molecule is made up of two atoms of hydrogen and one atom of oxygen. The molecules of water are arranged in such a way that, the negative hydrogen atom is attracted to the positive hydrogen atom and the overall structure is bent. Because oxygen is more electronegative than hydrogen, oxygen atom draws the shared electrons toward itself , this gives the oxygen end of the molecule a partial negative charge and the hydrogen end, a partial positive charge.

2. The correct option is: WITHOUT THE PROPER BALANCE OF WATER, CHEMICAL REACTIONS WILL NOT TAKE PLACE. Metabolic chemical reactions take place in living cells all the time because water, which is a necessary condition for the reaction is in place. Th fluids find in the cells are mostly water; water creates suitable conditions for biochemical reactions to take place. Without water, the cells will not be able to carry out any chemical reaction.

3. The correct option is A. Hydrogen bond allows oxygen and water molecules to be bonded together. Hydrogen bonds are weak interactions that formed between the hydrogen with a patial positive end and oxygen with a patial negative end. The hydrogen bond in water is responsible for the unique properties associated with water.

4 0

2 years ago