Answer:
Investigation B, Step 2
Explanation:
The <em>colour change</em> is a good indication of a <em>chemical change</em>. The sugar molecules were most likely changing into something else.
Investigation A, Step 1. <em>Wron</em>g. The dissolving of salt is a <em>physica</em>l process.
Investigation A, Step 2. <em>Wrong</em>. You simply boiled off the water (a <em>physical</em> process) and recovered the salt.
Investigation B, Step 1. <em>Wrong</em>. The dissolving of sugar is a <em>physical</em> process.
Answer and Explanation:
<u>D) 7 is the answer</u>
Together, the crust and the upper part of the mantle form the lithosphere, Earth's solid outer shell. This rocky, brittle layer is broken up into seven major and several minor tectonic plates (also known as lithospheric plates) that fit together like puzzle pieces.
<u><em>#teamtrees #PAW (Plant And Water)</em></u>
Answer:
Explanation:
We're asked to calculate the number of atoms of
Ca
in
153
g Ca
.
What we must first do is convert the given mass of calcium to moles of calcium, using its molar mass (referring to a periodic table, this is
40.08
g
mol
):
153
g Ca
(
1
mol Ca
40.08
g Ca
)
=
3.82
mol Ca
Using Avogadro's number,
6.022
×
10
23
particles
mol
, we can calculate the number of atoms present:
3.82
mol Ca
(
6.022
×
10
23
atoms Ca
1
mol Ca
)
=
2.30
×
10
24
atoms Ca
Answer: 11.0 g of calcium will react with 10.0 grams of water.
Explanation:
To calculate the moles, we use the equation:
moles of 
The balanced chemical equation is:
According to stoichiometry :
2 moles of require = 1 mole of 
Thus 0.55 moles of require=
of
Mass of 
Thus 11.0 g of calcium will react with 10.0 grams of water.
All copper atoms have atomic number 29: all their nuclei contain 29 protons. But they also contain uncharged particles called neutrons. ... The two different kinds of atom are called isotopes of copper. The neutron has a mass very similar to that of the proton, so the two isotopes differ in mass.
