Answer:
Option (2) 2
Explanation:
NO3- + 4H+ + Pb → Pb2+ + NO2 + 2H2O
The equation above can be balance as follow:
There are 3 atoms of the left side and a total of 4 atoms on the right side. It can be balance by putting 2 in front NO3- and 2 in front of NO2 as shown below:
2NO3- + 4H+ + Pb → Pb2+ + 2NO2 + 2H2O
Now the equation is balanced.
The coefficient of NO2 is 2
Answer:
The bismuth sample.
Explanation:
The specific heat
of a substance (might not be a metal) is the amount of heat required for heating a unit mass of this substance by unit temperature (e.g.,
.) The formula for specific heat is:
,
where
is the amount of heat supplied.
is the mass of the sample.
is the increase in temperature.
In this question, the value of
(amount of heat supplied to the metal) and
(mass of the metal sample) are the same for all four metals. To find
(change in temperature,) rearrange the equation:
,
.
In other words, the change in temperature of the sample,
can be expressed as a fraction. Additionally, the specific heat of sample,
, is in the denominator of that fraction. Hence, the value of the fraction would be the largest for sample with the smallest specific heat.
Make sure that all the specific heat values are in the same unit. Find the one with the smallest specific heat: bismuth (
.) That sample would have the greatest increase in temperature. Since all six samples started at the same temperature, the bismuth sample would also have the highest final temperature.
Answer:
1.2 atm
Explanation:
Given data
- Volume of the gas in the tank (V₁): 200.0 L
- Pressure of ethylene gas in the tank (P₁): ?
- Volume of the gas in the torch (V₂): 300 L
- Pressure of the gas in the torch (P₂): 0.8 atm
If we consider ethylene gas to be an ideal gas, we can find the pressure of ethylene gas in the tank using Boyle's law.

Density
=mass÷volume
=277÷38
=7.29 g/cm3