Answer:
B. 0.92 M
Explanation:
Molarity of a solution = number of moles (n) ÷ volume (V)
According to the information provided in this question;
mass of NaCl = 42g
Volume of water = 780mL
Using mole = mass/molar mass
Molar mass of NaCl = 23 + 35.5 = 58.5g/mol
mole = 42/58.5
mole (n) = 0.72mol
Volume (V) = 780 mL = 780/1000 = 0.780 L
Hence, molarity = n/V
Molarity = 0.72/0.780
Molarity = 0.923 M
Sound waves.
Radio waves and Microwaves are non-ionizing radiation. Gamma waves are ionizing radiation
B. 11,540
<h3>Further explanation
</h3>
The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.
Usually radioactive elements have an unstable atomic nucleus.
General formulas used in decay:
T = duration of decay
t 1/2 = half-life
N₀ = the number of initial radioactive atoms
Nt = the number of radioactive atoms left after decaying during T time
Nt=25 g
No=100 g
t1/2=5770 years
Answer:
1. 31.25 mL
2. 1.98 g/L
3. 0.45 g/mL
Explanation:
For each of the problems, you need to perform unit conversions. You need to use the information given to you to convert to a specific unit.
1. You need volume (mL). You have density (g/mL) and mass (g). Divide mass by density. You will cancel out mL and be left with g.
(50.0 g)/(1.60 g/mL) = 31.25 mL
2. You are given grams and liters. You need to find density with units g/L. This means that you have to divide grams by liters.
(0.891 g)/(0.450 L) = 1.98 g/L
3. You have to find density again but this time with units g/mL. Divide the given mass by the volume.
(10.0 g)/(22.0 mL) = 0.45 g/mL
