Answer:
0.485mol/kg
Explanation:
Molality is defined as the ratio of the number of moles of a solute to the kilogram of a solvent which is usually water.
Mass of NaBr = 10g
Molar mass of NaBr= 23+80=103g/mol
Mole of NaBr = mass / molar mass=10g/103g/mol= 0.097mol
Molality= Mole of a solute/ mass of solvent in kg
Mole of a solute( NaBr)= 0.097mol; mass of solvent( water in kg)= 200g. To convert to kg: 200g/1000g= 0.2kg
Molality = 0.097mol/0.2kg = 0.485mol/kg
Answer:
30, 50
Explanation:
Hello,
In this since an element's atomic number is equal to the number of protons in its atom, we can infer that selenium's atomic number is 30. Moreover, due to the fact the the neutrons are equal to the atomic mass minus the atomic number or the number of protons, by knowing the number of neutrons we compute the atomic as follows:
Thus, answer is 30, 50.
Best regards.
<h2>Answer:</h2>
<u>In dry climates, rates of evaporation exceed precipitation</u>
<h2>Explanation:</h2>
Evaporation is an important process in the global water cycle. Sunrays hits the surface of water or land and causes water to change state from a liquid to a gas. This is what we call evaporation. When evaporation occurs, at the same time precipitation occurs in the atmosphere which is the water falling from the clouds as rain, freezing rain, sleet, snow, or hail. As the rate of evaporation increases, the rate of precipitations increases too because both are connected to each other.
Answer:
The given metal is beryllium.
Explanation:
Given data:
Mass of metal = 74 g
Volume of metal = 40 cm³
Which metal is this = ?
Solution:
First of all we will calculate the density.
it is mass divided by volume.
d = m/v
d = 74 g/40 cm³
d = 1.85 g/cm³
In literature it is given that the density of beryllium is 1.85 g/cm³. Thus given metal is beryllium.
Answer:
brainliest plss
Explanation:
Photosynthesis is the process of converting light energy to chemical energy and storing it in the bonds of sugar. This process occurs in plants and some algae. Photosynthesis can be represented using a chemical equation.
