Answer:
Number 4 is an example of a chemical reaction
Explanation:
heThe chalk is reacting with the vingear which is creating a new substance. The new substance is the gas that the reaction gives off.
Direct Combination Reaction : The reaction in which two or more substances combine to form a single substance is called direct combination reaction. Synthesis Reaction: The reaction in which two or more elements combine to form a compound is called direct combination reaction.
HOPED I HELP BRIANEST PLZZ
Well some animals can survive in the dry land because they don't grow up by water
It is C. because the sunlight bounces off the moon causing it to be visible only at night.
Complete Question:
A chemist prepares a solution of silver (I) perchlorate (AgCIO4) by measuring out 134.g of silver (I) perchlorate into a 50.ml volumetric flask and filling the flask to the mark with water. Calculate the concentration in mol/L of the silver (I) perchlorate solution. Round your answer to 2 significant digits.
Answer:
13 mol/L
Explanation:
The concentration in mol/L is the molarity of the solution and indicates how much moles have in 1 L of it. So, the molarity (M) is the number of moles (n) divided by the volume (V) in L:
M = n/V
The number of moles is the mass (m) divided by the molar mass (MM). The molar mass of silver(I) perchlorate is 207.319 g/mol, so:
n = 134/207.319
n = 0.646 mol
So, for a volume of 50 mL (0.05 L), the concentration is:
M = 0.646/0.05
M = 12.92 mol/L
Rounded to 2 significant digits, M = 13 mol/L
