1. When our Galaxy was forming why was the center dense?
Answer: <u>Stars are believed to originate as from gas clouds in space. Gravitational forces cause this gas to contract forming a dense center of gravitational force.Eventually this extreme pressure at the center of the star causes nuclear fusion reactions to occur.</u>
2. Why did hydrogen atoms collide in the dense center of the Galaxy?
Answer: <u>Compression would heat the gas to temperatures above 1,000 kelvins. Some hydrogen atoms would pair up in the dense, hot gas, creating trace amounts of molecular hydrogen. The hydrogen molecules would then start to cool the densest parts of the gas by emitting infrared radiation after they collide with hydrogen atoms.</u>
Answer:
a. True
Explanation:
In the periodic table , all the elements are placed in a certain fashion , i.e. , with increasing atomic number.
Since ,
The element lithium and nitrogen are placed , in group 1 and 15 respectively.
as we go from left to right , across the group , the atomic radius decreases ,
Because ,
As , we go left to right , the number of electrons increases in the same shell , and proton too increases , which in turn increases the nuclear attraction , and the nucleus holds on to the electrons more firmly , and hence , the size reduces , as the electrons increases , in the same shell.
Hence, the given statement is true.
Answer:
En la imagen adjunta.
Explanation:
Hola.
En este caso, debemos recordar que la fórmula semi desarrollada se relaciona con la fórmula estructural del compuesto orgánico a representar; de este modo, primeramente encontramos una cadena de cinco carbonos con un doble enlace en el primer carbono y dos radicales metil tanto en el segundo como en el tercer carbono. Por otro lado, la formula global muestra el tipo y número de átomos presentes en el compuesto, que para el dado, son siete átomos de carbono y catorce de oxígeno, según se puede observar en la imagen adjunta.
¡Saludos!
Answer:
3.29 M
Explanation:
Molarity refers to the molar concentration of a solution and it can be calculated using the formula below:
Molarity (M) = number of moles (n) ÷ volume (V)
According to this question, the mass of HCl was given to be 60.4 grams and the volume of water as 505 mL.
Using mole = mass/molar mass to convert mass of HCl to moles
Molar mass of HCl = 1.0079 + 35.453 = 36.4609g/mol
mole = 60.4g ÷ 36.4609g/mol
mole = 1.66mol
Volume of water = 505mL = 505/1000 = 0.505L
Molarity, M = 1.66 ÷ 0.505
Molarity of HCl solution = 3.29 M
