Neurons- transmit nerve impulses. And Neuroglial cells- are non-conducting “support cells” of nervous tissue.
Answer:
D. Separating a salt solution by evaporating the water
Explanation:
B. Allowing a nail to rust is a chemical change.
Becuase once the nail rust it turns into flakes and therefore is no longer a nail.
C. building a model rocket propelled by mixing baking soda and vinegar
By mixing baking soda (a powder) into vinegar ( a Acid) it causes a explosion...
the baking soda dissolve into the acid.... This a chemical reaction
A.creating salt by reacting sodium metal and chlorine gas
Sodium is salt but it says.... Sodium metal..... chlorine gas Changes color and it has a strong odor... chlorine gas with sodium metal turns it into salt.... it doesnt stay a metal or a gas it CHANGES.....
so therefore its a Chemical change
When A object or substance changes form or it causes a exsplosion or reaction it is a chemical change.
D. Separating a salt solution by evaporating the water
For a physical change your object may change color or shape but its still the same object.
salt in water ... The salt dont dissolve it just salty water.
So seperating salt by evaporating the water is a physical change.
Answer:
H₄SiO₄
Explanation:
From the question given above, the following data were obtained:
Hydrogen (H) = 4 moles
Oxygen (O) = 4 moles
Silicon (Si) = 1 mole
Empirical formula =?
Since the number of mole of each atom of the element present is known, the empirical formula of the compound can be written as follow:
H₄SiO₄
Answer:
[NaOH] = 19.1 M
Last option.
Explanation:
Sodium hydroxide is available commercially as a 50.0% by weight aqueous solution.
50% by weight means, that in 100 g of solution we have 50 grams of solute.
Molar mass of solute: 40 g/m
Mass / Molar mass = moles
50 g / 40 g/m = 1.25 moles
These are the moles of solute in 100 grams of solution, so we must use density data, so we can find out our volume.
Solution density = Solution mass / Solution volume
1.53 g/mL = 100 g / Solution volume
Solution volume = 100 g / 1.53 g/mL
Solution volume = 65.3 mL
1.25 moles of solute are in 65.3 mL of solution
Molarity = moles /L
Let's convert 65.3 mL in L
65.3 / 1000 = 0.0653 L
1.25 moles /0.0653 L = 19.1 M
