All categories

2 years ago

If you can help answer the question if you can't then don't

Chemistry

1 answer:

vampirchik [111]2 years ago

4 0

Answer:

Yes its both a physical and chemical change heres why.

When heated , the wax melts to form a liquid wax . The liquid wax then becomes a solid wax upon cooling ( Physical change )

When the candle is lit, the wax near the tip of the candle will melt . The wick then absorbs the liquid wax . The liquid wax then vapourizes due to the heat emitting from the flame . The wax vapour then burns to give off a black substance ( what we will to as CO₂ , soot ) , heat and water vapour

(Chemical change )

Brainliest ? Hope I answered your question

You might be interested in

What mass of HBO2 is produced from the<br> combustion of 139.5 g of B2H6?<br> Answer in units of g.

aliina [53]

Answer:

$m_{HBO_2}=441.8gHBO_2$

Explanation:

Hello there!

In this case, since the combustion of B2H6 is:

$B_2H_6+3O_2\rightarrow 2HBO_2+2H_2O$

Thus, since there is 1:2 mole ratio between the reactant and product, the produced grams of the latter is:

$m_{HBO_2}=139.5gB_2H_6*\frac{1molB_2H_6}{27.67gB_2H_6} *\frac{2molHBO_2}{1molB_2H_6} *\frac{43.82gHBO_2}{1molHBO_2}$

$m_{HBO_2}=441.8gHBO_2$

Best regards!

5 0

2 years ago

What conclusion was a direct result of the gold foil experiment

vfiekz [6]

<span>An atom is composed of at least three types of subatomic particles. An electron has properties of both waves and particles. An atom is mostly empty space with a dense, positively charged nucleus.</span>

6 0

3 years ago

Why is melting point considered a physical property

miskamm [114]

Answer:

Because you can physically see the object melting when it comes to the melting point. The objects texture, color, temperature, shape, and state of matter (solid, liquid, gas) are possibly changing.

6 0

2 years ago

If 10.00 g of iron metal is burned in the presence of excess of O2 how many grams of Fe2O3 will form

sergiy2304 [10]

14.292 grams of Fe2O3 is formed when 10 gram of iron metal is burned.

Explanation:

The balanced equation for the reaction is to be known so that number of moles taking part can be known.

The balanced chemical equation is

4Fe + 3 $O_{2}$ ⇒ 2 $Fe{2}$ $O{3}$

From the given weight of iron to be used for the production of $Fe{2}$ $O{3}$ , number of moles of Fe taking part in the reaction can be known by the formula:

Number of moles= mass ÷ Atomic mass of one mole of the element.

(Atomic weight of Fe is 55.845 gm/mole)

Putting the values in equation

Number of moles = 10 gm ÷ 55.845 gm/mole

= 0.179 moles

Applying the stoichiometry concept

4 moles of Fe gives 2 Moles of Fe2O3

0.179 moles will produce x moles of Fe2O3

So, 2÷ 4 = x ÷ 0.179

2/4 = x/ 0.179

2 × 0.179 = 4x

2 × 0.179 / 4 = x

x = 0.0895 moles

So from 10 grams of iron metal 0.0895 moles of Fe2O3 is formed.

Now the formula used above will give the weight of Fe2O3

weight = atomic weight × number of moles

= 159.69 grams × 0.0895

= 14.292 grams of Fe2O3 formed.

4 0

2 years ago

One of the waste products produced by kidneys is creatinine. A healthy range ofcreatinine in human blood is between 0.50 mg/dL a

Anna35 [415]

The normal range of creatinine in human blood is between 0.50 mg/dL and 1.1 mg/dL. The patient's blood has a concentration of 0.0082 g/L. Let's convert that value into mg/dL.

We kwnot that there are 1000 mg in 1 g. And there are 10 dL in 1 L. We have to use those conversions.

1000 mg = 1 g 10 dL = 1 L

0.0082 g/L = 0.0082 g/L * 1000 mg/g = 8.2 mg/L * 1 L/ (10 dL) = 0.82 mg/dL

0.0082 g/L = 0.82 mg/dL

0.50 mg/dL < 0.82 mg/dL < 1.1 mg/dL

Answer: The concentration of creatinine = 0.82 mg/dL. It is in the normal range.

8 0

1 year ago