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2 years ago

2. Why do you think electroplated jewelleries are in demand? Chemistry plsss

Chemistry

1 answer:

Ivan2 years ago

8 0

Explanation:

Electroplated jeweleries are in demand because firstly they are as shiny and attractive as real jeweleries, they are also light weighted and cost effective.

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What is a graph?

Keith_Richards [23]

*Visual

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5 0

3 years ago

70 points and will give brainliest

ikadub [295]

Answer:

74mL

Explanation:

Given parameters:

Molar mass of citric acid = 192g/mol

Molar mass of baking soda = 84g/mol

Concentration of citric acid = 0.8M

Mass of baking powder = 15g

Unknown parameters:

Volume of citric acid = ?

Solution

Equation of the reaction:

C₆H₈O₇ + 3NaHCO₃ → Na₃C₆H₅O₇ + 3H₂O + 3CO₂

Procedure:

We work from the known parameters to the unknown. From the statement of the problem, we can approach the solution from the parameters of the baking powder.
From the baking powder, we can establish a molar relationship between the two reactants. We employ the mole concept in this regard.
We find the number of moles of the baking powder that went into the reaction using the expression below:

Number of moles = $\frac{mass}{molar mass}$

Number of moles = $\frac{15}{84}$ = 0.179mole

From the equation of the reaction, we can find the number of moles of the citric acid:

3 moles of baking powder reacted with 1 mole of citric acid

0.179 moles of baking powder would react with $\frac{0.179}{3}$ :

This yields 0.059mole of citric acid

To find the volume of the citric acid, we use the mole expression below:

Volume of citric acid = $\frac{number of moles}{concentration}$

Volume of citric acid = $\frac{0.059}{0.8}$ = 0.074L

Expressing in mL gives 74mL

4 0

3 years ago

14. Compare between the plasticity of edge and screw dislocations in BCC metals 15. Why does a screw dislocation in a BCC metal

Alenkasestr [34]

Answer:

14) The edge dislocation is more plastic than the screw dislocation

15) So as to form kinks that are fast moving

Explanation:

14) Edge and screw dislocations are the two main types of mobile dislocations

The three dimensional core of the screw dislocation prevents the slipping of the layers (one over the other) in a BCC metal such that kinks are required to be formed first by thermal activation (heating) in order. The kinks are edge dislocation that move such that the screw dislocation moves forward

Hence, the edge dislocation is more plastic than the screw dislocation

15) The three dimensional structure of a screw dislocation acts like a wedge which resists the slipping of the layers in the BCC structure such that the screw dislocation needs to be highly thermally activated forming kinks before the surrounding layers can move.

4 0

3 years ago

What inorganic molecule is carbon normally found in?

DiKsa [7]

It’s CO2

Carbon dioxide

6 0

3 years ago

Carbon-14 has a half-life of 5,700 years.

Maksim231197 [3]

Answer:

$3.106\ \text{g}$

Explanation:

$t_{1/2}$ = Half-life of carbon = 5700 years

t = Time at which the remaining mass is to be found = 10400 years

$m_0$ = Initial mass of carbon = 11 g

Decay constant is given by

$\lambda=\dfrac{\ln2}{t_{1/2}}$

Amount of mass remaining is given by

$m=m_0e^{-\lambda t}\\\Rightarrow m=m_0e^{-\dfrac{\ln2}{t_{1/2}} t}\\\Rightarrow m=11e^{-\dfrac{\ln 2}{5700}\times 10400}\\\Rightarrow m=3.106\ \text{g}$

The amount of the substance that remains after 10400 years is $3.106\ \text{g}$ .

5 0

3 years ago