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3 years ago

How many moles are in 1.93 x 10^24 atoms of gold

Chemistry

2 answers:

Anni [7]3 years ago

6 0

Answer:

We know that 1 mole equals to 6.02 x 10^23 atoms (which is Avogadro's number), so to get to atoms from moles, you would divide the atoms of gold by Avogadro's number

(1.93 x 10^24) / (6.02 x 10^23)

= 3.2 mol of gold (rounded)

pshichka [43]3 years ago

4 0

Answer:

do u still need the answer

Explanation:

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How many particles are in 1 mol of carbon? 1 mol of lithium? 1 mol of eggs? will 1 mol of each of these substances have the same

andrezito [222]

One mole of a substance contains Avogadro's number of atoms/molecules/the like. This would mean that all of the items described would have approximately 6.022 * 10^23 atoms, even though their masses would differ. This would be due to the molar mass of each substance being different because of the constituent elements in the substance.

8 0

3 years ago

What is the most reactive element

SashulF [63]

Answer:

fluorine

Explanation:

3 0

3 years ago

1s22s²2p63s23p64s²3d104p5 Which element is this?

bearhunter [10]

Answer: bromine

Explanation:

There are a total of 2+2+6+2+6+2+10+5=35 electrons, meaning there are 35 protons. The element with atomic number 35 is bromine

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2 years ago

When a 235 92U nucleus is bombarded by neutrons (10n) it undergoes a fission reaction, resulting in the formation of two new nuc

user100 [1]

Answer:

$^{139}_{56}Ba$

Explanation:

The fission reaction taking place given in the question is:

$^{235}_{92}U+^{1}_{0}n\rightarrow ^{A}_{Z}Ba+^{94}_{36}Kr+3^{1}_{0}n$

The mass is conserved in the reaction.

So,

235 + 1 = A + 94 + 3×1

A = 139 g/mol

Also, number o protons remain same. So,

92 = Z + 36

Z = 56

The isotopic symbol is $^{139}_{56}Ba$

5 0

3 years ago

The average C - H bond energy in CH4 is 415 kJ / mol. Use the following data to calculate the average C - H bond energy in ethan

sertanlavr [38]

Answer and Explanation:

ΔH = (Bond energies of the products) - (Bond Energies of the reactants)

a) C2H6 + H2 ----> 2CH4 ΔH = -65.07 KJ/mol

Bond energy of product = 2×Bond energy of CH4 =2 × (4 (C-H)) =2 × 4 × 415 = 3320 KJ/mol

Bond energy of reactants = Bond energy of C2H6 + Bond energy of H2

Bond energy of C2H6 = (C-C) + 6(C-H) = 347 + 6(C-H)

Bond energy of H2 = (H-H) = 432 KJ/mol

-65.07 = 3320 - (Bond energy of C2H6 + 432)

Bond energy of C2H6 = 3320-432+65.07 = 2953.07 KJ/mol

Bond energy of C2H6 = (C-C) + 6(C-H) = 347 + 6(C-H) = 2953.07

(C-H) = (2953.07 -347)/6 = 434.345 KJ/mol

b) C2H4 + 2H2 ------> CH4 ΔH = -202.21 KJ/mol

Bond energy of product = 2×Bond energy of CH4 =2 × (4 (C-H)) =2 × 4 × 415 = 3320 KJ/mol

Bond energy of reactants = Bond energy of C2H4 + (2 × Bond energy of H2)

Bond energy of C2H4 = (C=C) + 4(C-H) = 614 + 4(C-H)

(2 × Bond energy of H2) = 2 × 432 = 864 KJ/mol

-202.21 = 3320 - (Bond energy of C2H4 + 864)

Bond energy of C2H4 = 3320+202.21-864 = 2658.1 KJ/mol

Bond energy of C2H4 = (C=C) + 4(C-H) = 614 + 4(C-H) = 2658.1

(C-H) = (2658.1 - 614)/4 = 511.05 KJ/mol

c) C2H2 + 3H2 ------> 2CH4 ΔH = -376.74 KJ/mol

Bond energy of product = 2×Bond energy of CH4 =2 × (4 (C-H)) =2 × 4 × 415 = 3320 KJ/mol

Bond energy of reactants = Bond energy of C2H2 + (3 × Bond energy of H2)

Bond energy of C2H = (triple bond Carbon to Carbon) + 2(C-H) = 839 + 2(C-H)

(3 × Bond energy of H2) = 3 × 432 = 1296 KJ/mol

-376.74 = 3320 - (Bond energy of C2H2 + 1296)

Bond energy of C2H2 = 3320+376.74-1296 = 2400.74 KJ/mol

Bond energy of C2H2 = (triple bond Carbon to Carbon) + 2(C-H) = 839 + 2(C-H) = 2400.74

(C-H) = (2400.74 - 839)/2 = 780.87 KJ/mol

QED!!!

6 0

4 years ago