Answer:
This question lacks options, the options are;
A. Absorption of heat
B. A chemical change
C. A physical change
D. Formation of a new compound
The answer is C. A physical change
Explanation:
A physical change is a type of change that does not involve the chemical composition of the substance(s) involved. Physical changes affect the form but not the chemical content of a substance. Examples of physical changes are freezing, change of state, boiling etc.
In this question, a liquid is cooled during an investigation causing it to solidify. The cooling of this liquid represents a PHYSICAL CHANGE because the liquid state of the substance is only changed to a solid state but does not involve changing the chemical composition of the substance.
The "Van Gogh" one is subjective, because it expresses opinion and is not a true, hard fact. :)
Answer:
5.41 x 10²² g
Explanation:
Data Given:
no. of moles of sodium = 2.35 x 10²¹ moles
mass of sodium = ?
Solution:
Formula used
no. of moles = mass in grams / molar mass
To find mass rearrange the above equation:
mass in grams = no. of moles x molar mass. . . . . . (1)
- molar mass of Sodium (Na) = 23 g/mol
Put values in equation 1
mass in grams = 2.35 x 10²¹ moles x 23 g/mol
mass in grams = 5.41 x 10²² g
So,
mass of Sodium (Na) = 5.41 x 10²² g
This should help hopefully
Either NaI or INa are acceptable formulae for sodium iodide, which is indeed a binary ionic compound. So, the correct answer would be B.
