All categories

4 years ago

What defining feature makes a material an insulator?

1 answer:

3 0

A defining feature of a material that is a good insulator would be its ability to stop or cancel an electric charge of another material. This happens because the molecules in the material are stable and there are no free electrons that would allow the charges to flow.

You might be interested in

Sand dunes protect beaches against erosion and flooding due to storms.

kogti [31]

Answer:

B. Building houses near the beach

Explanation:

it was right on edge

7 0

4 years ago

Read 2 more answers

In which reaction does the oxidation number of hydrogen change? In which reaction does the oxidation number of hydrogen change?

dedylja [7]

Answer: The correct answer is $2Na(s)+2H_2O(l)\rightarrow 2NaOH(aq.)+H_2(g)$

Explanation:

Oxidation number is defined as the number which is given to an atom when it looses or gains electron. When an atom looses electron, it attains a positive oxidation state. When an atom gains electron, it attains a negative oxidation state.

Oxidation state of the atoms in their elemental state is considered as 0. Hydrogen is present as gaseous state.

For the given chemical reactions:

Reaction 1: $2HClO_4(aq.)+CaCO_3(s)\rightarrow Ca(ClO_4)_2(aq.)+H_2O(l)+CO_2 (g)$

Oxidation state of hydrogen on reactant side: +1

Oxidation state of hydrogen on product side: +1

Thus, the oxidation state of hydrogen is not changing.

Reaction 2: $CaO(s)+H_2O(l)\rightarrow Ca(OH)_2(s)$

Oxidation state of hydrogen on reactant side: +1

Oxidation state of hydrogen on product side: +1

Thus, the oxidation state of hydrogen is not changing.

Reaction 3: $HCl(aq.)+NaOH(aq.)\rightarrow NaCl(aq.)+H_2O(l)$

Oxidation state of hydrogen on reactant side: +1

Oxidation state of hydrogen on product side: +1

Thus, the oxidation state of hydrogen is not changing.

Reaction 4: $2Na(s)+2H_2O(l)\rightarrow 2NaOH(aq.)+H_2(g)$

Oxidation state of hydrogen on reactant side: +1

Oxidation state of hydrogen on product side: 0

Thus, the oxidation state of hydrogen is changing.

Reaction 5: $SO_2(g)+H_2O(l)\rightarrow H_2SO_3(aq.)$

Oxidation state of hydrogen on reactant side: +1

Oxidation state of hydrogen on product side: +1

Thus, the oxidation state of hydrogen is not changing.

Hence, the correct answer is $2Na(s)+2H_2O(l)\rightarrow 2NaOH(aq.)+H_2(g)$

6 0

3 years ago

The elements of a delta Hf of ___ kj\mole at standard temp and pressure

EastWind [94]

Answer:

One mole of a substance forms Instead of standard atmospheric pressure and temperature from its pure elements{ conditions being the same} then this change and enthalpy is known as enthalpy of formation.

Explanation:

The equation of this formation can let us know what actually happens

ΔH = ΔHf(products) - ΔHf (reactants)

Hence we can say this change in enthalpy formation is the difference between the sum of product and sum of reactants.

6 0

3 years ago

Help asap help show work I need an A

MrRissso [65]

Answer: 17 (a) 360,000 ms 18 (a) 0.245 s

(b) 4.800 kg (b) 500 cm

(c) 560.0 dm (c) 68.00 m

(d) 72,000 mg (d) 0.025 Mg

Explanation:

Use the following table. Note the direction you are going to:

Right means move decimal to the right. Left means move decimal to the left.