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4 years ago

Which is a property of gold?

Chemistry

2 answers:

azamat4 years ago

8 0

Good conductor of electricity

den301095 [7]4 years ago

3 0

Good conductor of electricity

You might be interested in

How many mm are in 5 m

Alla [95]

1 meter = 1000mm

* 5

5 meters = 5000mm

6 0

3 years ago

Read 2 more answers

The density of wind-packed snow is estimated to be 0.35 g/cm^3. A flat roof that is 35 by 43 feet has 28 inches of snow on it. H

xz_007 [3.2K]

Answer:

There are 76728.2 pounds of snow on the roof

Explanation:

To determine how many pounds of snow are on the roof,

First we will determine the mass of the snow in grams.

From the question,

Density of snow = 0.35 g/cm³

From

Density = Mass / Volume

To determine the mass, we will first find the volume.

From the question, a flat roof that is 35 by 43 feet has 28 inches of snow on it, that is, the height of the snow on the roof is 28 inches.

Area of the roof = 35 ft × 43 ft = 1505 ft²

Volume of the snow = Area of the roof × Height of the snow

Height of the snow = 28 inches

12 inches = 1 foot

∴ 28 inches = 28/12 feet = 2.3333 ft

Hence,

Volume of the snow = 1505 ft² × 2.3333 ft = 3511.62 ft³

Volume of the snow = 3511.62 ft³

This is the volume of the snow in cubic feet

Now, we will convert cubic feet (ft³) to cubic centimeter (cm³)

1 ft = 30.48 cm

and 1 ft³ = 30.48³ cm³ = 28316.84659 cm³.

If 1 ft³ = 28316.84659 cm³

∴ 3511.62 ft³ will be 3511.62 × 28316.84659 cm³ = 99438004.83 cm³

Hence, Volume of snow = 99438004.83 cm³

Now, we can determine mass of snow in grams

From

Density = Mass / Volume

Mass = Density × Volume

Mass = 0.35 g/cm³ × 99438004.83 cm³

Mass = 34803301.69 g

Now, we will convert the mass from grams to pounds

1 pound = 453.592 grams

If 453.592 grams = 1 pound

Then, 34803301.69 g will be 34803301.69 / 453.592 pounds = 76728.2 pounds

Hence, there are 76728.2 pounds of snow on the roof.

6 0

3 years ago

Calculate the enthalpy for this reaction: 2C(s) + H2(g) ---> C2H2(g) ΔH° = ??? kJ Given the following thermochemical equation

nordsb [41]

Answer:

The enthalpy for given reaction is 232 kilo Joules.

Explanation:

$C_2H_2(g) + \frac{5}{2}O_2(g)\rightarrow 2CO_2(g) + H_2O(l), \Delta H^o_{1} = -1,123 kJ$ ...[1]

$C(s) + O_2(g)\rightarrow CO2(g), \Delta H^o_{2} = -340 kJ$ ..[2]

$H_2(g) + \frac{1}{2}O_2(g)\rightarrow H_2O(l) ,\Delta H^o_{3} = -211 kJ$ ..[3]

$2C(s) + H_2(g)\rightarrow C_2H_2(g),\Delta H^o_{4} =?$ ..[4]

2 × [2] + [3] - [1] ( Using Hess's law)

$\Delta H^o_{4}=2\times \Delta H^o_{2}+\Delta H^o_{3} - \Delta H^o_{1}$

$\Delta H^o_{4}=2\times (-340 kJ) + (-211 kJ) - (-1,123 kJ)$

$\Delta H^o_{4}=232 kJ$

The enthalpy for given reaction is 232 kilo Joules.

5 0

3 years ago

How is the molecule of substance formed

rosijanka [135]

Answer:

When atoms approach one another closely, the electron clouds interact with each other and with the nuclei. If this interaction is such that the total energy of the system is lowered, then the atoms bond together to form a molecule.

Explanation:

8 0

3 years ago

Calculate the pH of the resulting solution if 32.0 mL of 0.320 M HCl(aq) is added to (a) 42.0 mL of 0.320 M NaOH(aq). (b) 22.0 m

monitta

Answer:

a) pH = 11.5

b) pH= 3

Explanation:

a) lets calculate the number of moles of each reactant

moles of HCl = 32/1000 * 0.32 = 0.01024 mole

moles of NaOH = 42/1000 * 0.32 = 0.01344 moles

1 moles of HCl reacts with 1 moles of NaOH , so 0.01024 mole of HCl should react with 0.01024 moles of NaOH , but there is some excess NaOH.

excess NaOH= 0.01344 -0.01024 = 0.0032 moles

[H+]= $\frac{10^{-14} }{0.0032} = 3.125 *10^{-12}$

pH= -log [3.125*10^-12) = 11.5

b) moles of NaOH = 0.00924

excess HCl present = 0.01024 - 0.00924 =.001

so excess [H+] = 0.001

pH= -log( 0.001) = 3

3 0

3 years ago