1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
tester [92]
3 years ago
6

Wat the answer wat do i do here

Chemistry
2 answers:
suter [353]3 years ago
7 0
1. Hand Lens
2. Observing
VMariaS [17]3 years ago
6 0

you write

it said i need at lest 20 characters so here you go

You might be interested in
How much<br>much hydrogen gas evolved<br>when 1.5 current is passed through water for 1.5 hours?​
evablogger [386]

0.042 moles of Hydrogen evolved

<h3>Further explanation</h3>

Given

I = 1.5 A

t = 1.5 hr = 5400 s

Required

Number of Hydrogen evolved

Solution

Electrolysis of water ⇒ decomposition reaction of water into Oxygen and Hydrogen gas.

Cathode(reduction-negative pole) : 2H₂O(l)+2e⁻ ⇒ H₂(g)+2OH⁻(aq)

Anode(oxidation-positive pole) : 2H₂O(l)⇒O₂(g)+4H⁻(aq)+4e⁻

Total reaction : 2H₂O(l)⇒2H₂(g)+O₂(g)

So at the cathode H₂ gas is produced

Faraday : 1 mole of electrons (e⁻) contains a charge of 96,500 C

\tt mol~e^-=\dfrac{Q}{96500}

Q = i.t

Q = 1.5 x 5400

Q = 8100 C

mol e⁻ = 8100 : 96500 = 0.084

From equation at cathode , mol ratio e⁻ : H₂ = 2 : 1, so mol H₂ = 0.042

4 0
3 years ago
What is the general trend for valence electrons as you go across the periodic table left to right
Margarita [4]
The atomic radius decreases across a period from left to right and increases down a given group. The atoms with the largest atomic radii are located in group l and at the bottom of groups. Moving from left to right across a period, electrons are added one at a time to the outer energy shell. Hope this helps!
6 0
3 years ago
What is the composition, in atom percent, of an alloy that contains a) 45.5 lbm of silver, b) 83.7 lbm of gold, and c) 6.3 lbm o
lyudmila [28]

Answer:

\% atAg=44.6\%\\\% atAu=44.9\%\\\% atCu=10.5\%

Explanation:

Hello,

In this case, for computing the atom percent, one must obtain the number of atoms of silver, gold and copper as shown below:

atomsAg=45.5lbm*\frac{453.59g}{1lbm}*\frac{1molAg}{107.87gAg}*\frac{6.022x10^{23}atomsAg}{1molAg}=1.15x10^{26}atomsAg\\atomsAu=83.7lbm*\frac{453.59g}{1lbm}*\frac{1molAu}{196.97gAu}*\frac{6.022x10^{23}atomsAu}{1molAu}=1.16x10^{26}atomsAu\\atomsCu=6.3lbm*\frac{453.59g}{1lbm}*\frac{1molAg}{63.55gCu}*\frac{6.022x10^{23}atomsCu}{1molCu}=2.71x10^{25}atomsCu

Thus, the atom percent turns out:

\% atAg=\frac{1.15x10^{26}}{1.15x10^{26}+1.16x10^{26}+2.71x10^{25}}*100\% =44.6\%\\\% atAu=\frac{1.16x10^{26}}{1.15x10^{26}+1.16x10^{26}+2.71x10^{25}}*100\% =44.9\%\\\% atCu=\frac{2.71x10^{25}}{1.15x10^{26}+1.16x10^{26}+2.71x10^{25}}*100\% =10.5\%

Best regards.

4 0
3 years ago
A sample of helium has a volume of 50.00 L at STP. How many helium atoms are in the sample? Show work
Setler79 [48]

Answer:

Explanation:

molar volume at STP=22.4 L

given volume=50.0 L

number of moles=given volume/molar volume

number of moles=50.0/22.4

number of moles=2.2

1 mole of helium =6.023*10^23 atoms

2.2 moles of helium =6.023*10^23*2.2=1.3*10^24

therefore 50.0 L of helium contain 1.33*10^24 atoms

4 0
3 years ago
What is the definition of lead in chemistry
abruzzese [7]

Answer:

Lead is a chemical element with the symbol Pb (from the Latin plumbum) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point.

Explanation:

6 0
3 years ago
Other questions:
  • The number of protons in an atom is defined by it's
    8·1 answer
  • Help 10
    7·2 answers
  • The nucleus of an atom is
    11·2 answers
  • Recognizing the Properties of Water
    5·2 answers
  • NH3 + HCI —&gt; NH4CI synthesis O decomposition O single replacement O double replacement​
    12·1 answer
  • Is c6h12o6 an empirical formula?
    8·1 answer
  • What kind of cells do animals have?
    7·1 answer
  • Jupiter's gravity is about 2.3 times stronger than Earth's gravity Calculate the mass and
    12·1 answer
  • Student added a strip of aluminium metal in aqueous copper(2)Sulfate but no reaction occured. Suggest a reason why.
    5·1 answer
  • All the following process produces hematite except
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!