Explanation:
ns. sifat yg cukup cantik cewek berjilbab bisa buat apa benar bahwa beliau berkata begitu berat badannya nya nanti mereka masih menjadi merek kita ketahui ke kamar kost khusus nya yang mana ada komentar ke kantor kecamatan km mulai membuka kembali mm
Answer:
It can either release energy or take in energy.
Explanation:
In an exothermic reaction, the energy is released from the reaction and is typically released through the energy of heat or light.
In an endothermic reaction, the energy is absorbed by the reaction and often results in the chemical reaction becoming cold.
Answer:
The correct answer would be - 13.0975 ounces.
Explanation:
We know that brass is made up of zinc and copper. The copper part of the brass is approximately around 50 to 70% and the remaining is the zinc part.
Given:
Zinc percentage in a brass = 35%
copper percentage would be - 65% (100 - 35 = 65)
Weight of the brass metal bar = 20.15 ounce
ounces of copper are in the bar = ?
Solution:
The weight of the copper in the brass metal in ounces-
= weight of brass* percentage of copper/100
= 20.15*65/100
= 13.0975 ounces of copper.
2nd method =
The weight of the zinc in the brass metal in ounces-
= weight of brass* percentage of zinc/100
= 20.15*35/100
= 7.0525
The weight of the copper = total weight - weight of zinc
= 13.0975 ounces of copper.
Answer:
1.05 x 10²²atoms
Explanation:
Given parameters:
Mass of Pb = 3.6g
Unknown:
Number of atoms in Pb = ?
Solution:
Some very essential constants;
1 mole of a substance contains 6.02 x 10²³atoms/mole
Molar mass of Pb = 207.2g/mol
First, we convert the mass to number of moles then to number of atoms.
Number of moles =
3.6g x x x 6.02 x 10²³ x = 1.05 x 10²²atoms