Answer:
Protons and neutrons
Explanation:
The particles to forms the nucleus of an atom are the protons and neutrons of the atoms.
These materials are located in the tiny nucleus and contributes the most mass of the atom.
- Protons are the positively charged particles in an atom
- Neutrons do not carry any charges.
- Sum of the protons and neutrons gives the mass number of the atom.
Answer:
-26.125 kj
Explanation:
Given data:
Mass of water = 250.0 g
Initial temperature = 30.0°C
Final temperature = 5.0°C
Amount of energy lost = ?
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = T2 - T1
ΔT = 5.0°C - 30.0°C
ΔT = -25°C
Specific heat of water is 4.18 j/g.°C
Now we will put the values in formula.
Q = m.c. ΔT
Q = 250.0 g × 4.18 j/g.°C × -25°C
Q = -26125 j
J to kJ
-26125 j ×1 kj /1000 j
-26.125 kj
13111 is already an integer (whole number). It also can be expressed as 1 ton or 13111000g.
This problem is providing us with the volume of nitric acid that is titrated with 0.18 L of 0.1-M sodium hydroxide and asks for the concentration of the acid. At the end, the result turns out to be 0.045M, according to the following.
<h3>Acid-base titrations:</h3>
In chemistry, acid-base titrations allow us to quantify the volume or concentration of an acid or base via the following equation:

Where the subscript A stands for the acid and B for the base; which means one can calculate any of the variables there by knowing the other three. This equation is based on the balanced neutralization chemical equation, which takes place between the acid and the base.
Thus, we can write the reaction between NaOH and HNO3 as:

In such a way, we can solve for the concentration of the acid as shown below:

Learn more about titration: brainly.com/question/25485091
The answer is 19.9 grams cadmium.
Assuming there was no heat leaked from the system, the heat q lost by cadmium would be equal to the heat gained by the water:
heat lost by cadmium = heat gained by the water
-qcadmium = qwater
Since q is equal to mcΔT, we can now calculate for the mass m of the cadmium sample:
-qcadmium = qwater
-(mcadmium)(0.850J/g°C)(38.6°C-98.0°C)) = 150.0g(4.18J/g°C)(38.6°C-37.0°C)
mcadmium = 19.9 grams