Answer:
Most spiral galaxies consist of a flat, rotating disk containing stars, gas and dust, and a central concentration of stars known as the bulge. ... The spiral arms are sites of ongoing star formation and are brighter than the surrounding disc because of the young, hot OB stars that inhabit them.
Explanation:
An acid a. has a high pH in solution.
b. turns blue litmus paper to red.
c. releases hydroxyl ions in solution.
d. has more hydroxyl than hydrogen (or hydronium) ions.
<span>An acid </span>turns blue litmus paper to red. The answer is letter B.
Answer:
The percentage abundance of Eu isotopes are 52 % and 48 %
.
Explanation:
The formula for the calculation of the average atomic mass is:
Given that:
Since the element has only 2 isotopes, so the let the percentage of first be x and the second is 100 -x.
For first isotope,:
% = x %
Mass = 151.0 amu
For second isotope :
% = 100 - x
Mass = 153.0 amu
Given, Average Mass = 151.96 amu
Thus,
Solving for x, we get that:
x = 52 %
<u>Thus percentage abundance of Eu isotopes are 52 % and 48 %
.</u>
There are 1.92 × 10^23 atoms Mo in the cylinder.
<em>Step 1</em>. Calculate the <em>mass of the cylinder
</em>
Mass = 22.0 mL × (8.20 g/1 mL) = 180.4 g
<em>Step 2</em>. Calculate the<em> mass of Mo
</em>
Mass of Mo = 180.4 g alloy × (17.0 g Mo/100 g alloy) = 30.67 g Mo
<em>Step 3</em>. Convert <em>grams of Mo</em> to <em>moles of Mo
</em>
Moles of Mo = 30.67 g Mo × (1 mol Mo/95.95 g Mo) = 0.3196 mol Mo
<em>Step 4</em>. Convert <em>moles of M</em>o to <em>atoms of Mo
</em>
Atoms of Mo = 0.3196 mol Mo × (6.022 × 10^2<em>3</em> atoms Mo)/(1 mol Mo)
= 1.92 × 10^23 atoms Mo
Answer:
Covalent bonding
Explanation:
In covalent bonding, the electrons are shared to fill the octet rule (8 electrons in valence shell). CCl4 tends to do covalent bonding because the the 4 valence electrons are Carbon are shared with the Chlorine atoms so that each chlorine atom has a full octet and chlorine shares its electrons to fill the octet of carbon.
Also, since carbon and chlorine are both non-metal, non-metal things exhibit covalent bonding thus this is covalent bonding as well. Ionic boding is for metal and non metal pair where electrons are transferrred, in our case, electrons are shared, they are not transferred.
