The modern periodic table is arranged by increasing

1 answer:

5 0

The periodic table of elements arranges all of the known chemical elements in an informative array. Elements are arranged from left to right and top to bottom in order of increasing atomic number. Order generally coincides with increasing atomic mass. The rows are called periods.

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What is the isotope notation of the element that has an atomic number of 24 and a mass number of 52?

Fofino [41]

Answer:

Chromium

Explanation:

Cr has 24 atomic number and mass number 52

4 0

3 years ago

I would be so grateful if someone helped me with my lab report. My lab report is about identifying unknown solids.

kipiarov [429]

Answer:

good afternoon

Explanation:

like that you dummy

3 0

3 years ago

Which of the following is the correct balanced equation for the reaction in which methane (CH4) burns in atmospheric oxygen (0₂)

Talja [164]

Answer: $\text{CH}_{4}+2\text{O}_{2} \longrightarrow \text{CO}_{2}+2\text{H}_{2}\text{O}$

Explanation:

The unbalanced equation is

$\text{CH}_{4}+\text{O}_{2} \longrightarrow \text{CO}_{2}+\text{H}_{2}\text{O}$

Balancing this equation, we get:

$\boxed{\text{CH}_{4}+2\text{O}_{2} \longrightarrow \text{CO}_{2}+2\text{H}_{2}\text{O}}$

8 0

2 years ago

Why does the mass number for an element differ from the average atomic mass for the element?

yarga [219]

Answer:

the mass number is the number of protons and neutrons added and the average atomic mass is the weight of the protons and neutrons

4 0

3 years ago

The atomic masses of 151eu and 153eu are 150.919860 and 152.921243 amu, respectively. The average atomic mass of europium is 151

vitfil [10]

Answer:- The natural abundance of $^1^5^1_E_u$ is 0.478 or 47.8% and $^1^5^3_E_u$ is 0.522 or 52.2% .

Solution:- Average atomic mass of an element is calculated from the atomic masses of it's isotopes and their abundances using the formula:

Average atomic mass = mass of first isotope(abundance) + mass of second isotope(abundance)

We have been given with atomic masses for $^1^5^1_E_u$ and $^1^5^3_E_u$ as 150.919860 and 152.921243 amu, respectively. Average atomic mass of Eu is 151.964 amu.

Sum of natural abundances of isotopes of an element is always 1. If we assume the abundance of $^1^5^1_E_u$ as n then the abundance of $^1^5^3_E_u$ would be 1-n .

Let's plug in the values in the formula:

$151.964=150.919860(n)+152.921243(1-n)$