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
Dmitriy789 [7]
3 years ago
14

From 1962 until 1981 pennies were made from 95% copper and 5% zinc and had a mass of 3.1 g. Starting in 1982, pennies have been

made from 97.5% zinc and 2.5% copper and have a mass of 2.5 g. Suppose you have a sample of pennies that consists of 45.4% pre-1982 pennies. Determine the average mass of a penny in this sample.
Chemistry
1 answer:
Sloan [31]3 years ago
8 0

Answer:

2.7724 g

Explanation:

Mass of pre- 1892 pennies = 3.1 g

Abundance = 45.4 %

Mass of post 1892 pennies = 2.5 g

Abundance = 100 - 45.4 = 54.6 %

The average mass is given as = ( 3.1 g   *  45.4 / 100)  +  (2.5g  *  54.6 / 100)

Average Mass = 3.1 * 0.454   +   2.5  *  0.546

Average Mass = 1.4074  + 1.365 = 2.7724 g

You might be interested in
The alveoli are surrounded by __________ carrying blood to and from the heart.
natka813 [3]
The alveoli are surrounded<span> by tiny blood vessels, called capillaries. The </span>alveoli<span> and capillaries both have very thin walls, which allow the oxygen to pass from the </span>alveoli<span>to the blood. The capillaries then connect to larger blood vessels, called veins, which bring the oxygenated blood from the lungs to the heart.</span>
4 0
2 years ago
What is the initial temperature of a gas if the volume changed from 1.00 l to 1.10 l and the final temperature was determined to
Feliz [49]
Using charles law
v1/t1=v2/t2
v1=1l
v2=1.1l
t2=255+273=528
t1=?
1/t1=1.1/528   
cross multiply
1.1t1=528 divide both sides by 1.1
t1=528/1.1
t1=480k or 207celcius
5 0
3 years ago
Read 2 more answers
In this reaction, what is the substance oxidized? zn(s) + 2 hcl(aq) → zncl2(aq) + h2(g) zinc chloride chlorine hydrogen zn oxyge
Zarrin [17]
Zn(s) + 2 HCl(aq) → ZnCl₂(aq) + H₂(g) 
Oxidation means lose of electrons and increase of positive charge so the part which oxidized in this equation is Zn(s) because it converted to Zn²⁺ (i.e. lost two electrons) 
7 0
3 years ago
Read 2 more answers
If the volume occupied by the air in a bicycle pump is 525 cm3, and the pressure changes from 73.2 kPa to 122.5 k.Pa as the pist
Musya8 [376]

Answer:

V_2=313.71\ cm^3

Explanation:

Given that,

Initial volume, V_1=525\ cm^3

The pressure changes from 73.2 kPa to 122.5 k.Pa.

We need to find the new volume occupied by the air. Let it is V₂. It can be calculated using Boyle's law such that,

P_1V_1=P_2V_2\\\\V_2=\dfrac{P_1V_1}{P_2}\\\\V_2=\dfrac{73.2\times 525}{122.5}\\\\V_2=313.71\ cm^3

So, the new volume is 313.71\ cm^3.

6 0
2 years ago
How does the behavior of a high-energy particle compare to a low-energy particle?
irina1246 [14]

Answer:

The problem of energy exchange between waves and particles, which leads to energization of the latter, in an unstable plasma typical of the radiation belts. The ongoing Van Allen Probes space mission brought this problem among the most discussed in space physics. A free energy which is present in an unstable plasma provides the indispensable condition for energy transfer from lower energy particles to higher-energy particles via resonant wave-particle interaction. This process is studied in detail by the example of electron interactions with whistler mode wave packets originated from lightning-induced emission. We emphasize that in an unstable plasma, the energy source for electron energization is the energy of other particles, rather than the wave energy as is often assumed. The way by which the energy is transferred from lower energy to higher-energy particles includes two processes that operate concurrently, in the same space-time domain, or sequentially, in different space-time domains, in which a given wave packet is located. In the first process, one group of resonant particles gives the energy to the wave. The second process consists in wave absorption by another group of resonant particles, whose energy therefore increases. We argue that this mechanism represents an efficient means of electron energization in the radiation belts.

Explanation:

Fun facts:

In the process of energy transfer between two groups of particles both processes operate simultaneously, and if the lower energy part of plasma distribution gives energy to the wave while the higher‐energy part absorbs the wave enrgy, then the wave‐mediated energy transfer from lower energy particles to higher‐energy ...

5 0
3 years ago
Other questions:
  • Consider the cell pt | h2 (1 atm); h+ (? m) || hg2cl2(s); cl− (1 m) | hg 2 h+ + 2 e − → h2 e 0 = 0.00 v hg2cl2 + 2 e − → 2 hg +
    12·2 answers
  • How many moles of He are in 16 g of the element? 1.0 mol 4.0 mol 8.0 mol 16 mol
    9·1 answer
  • How have new technologies made it easier for scientists around the world to share ideas with each other?
    10·1 answer
  • An unknown metal has a density of 10.51 g/ml and a mass of 287.8 g. What is the
    12·2 answers
  • How many moles of salt will you be using in this recipe?​
    15·1 answer
  • The graph shows a car's velocity over time. Velocity versus Time 60 40 Velocity, in mph forward 30 20 10 4 1 2 3 5 G Time, in se
    9·2 answers
  • Barium bromide dissolves in water. Which statement is true?
    13·1 answer
  • A diprotic acid (H2X) titrated with a solution of NaOH for 25 ml of the acid 87.42 ml of a 1.95 M solution of NaOH was required
    6·1 answer
  • Will give brainliest, to whoever gets right. If you do a random answer I will report it.
    9·1 answer
  • Hi can someone please help me find the average for these temperatures? I need them asap
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!