Answer:
The missing reagents are.
Potassium + Iodine =<u> Potassium iodide</u>
<u>Calcium</u> + oxygen = Calcium oxide
Beryllium +<u> Bromine</u> = Beryllium bromide
<u>Copper + Oxygen</u> = Copper oxide
Explanation:
The balanced equation can be written as:
1.Potassium + Iodine =<u> Potassium iodide</u>

Here K = potassium
I2 = Iodine
KI = potasssium iodide.
2.<u>Calcium</u> + oxygen = Calcium oxide

Ca = calcium
O2 = oxygen
CaO = Calcium Oxide
3.Beryllium +<u> Bromine</u> = Beryllium bromide

Here,
Be = beryllium
Br2 = bromine
BeBr2 = Beryllium Bromide
4. Copper + Oxygen = Copper oxide

Cu = Copper
O2 = oxygen
CuO = Copper Oxide
Answer:
Covalent bonds usually occur between nonmetals. For example, in water (H2O) each hydrogen (H) and oxygen (O) share a pair of electrons to make a molecule of two hydrogen atoms single bonded to a single oxygen atom. ... Covalent compounds tend to be soft, and have relatively low melting and boiling points.
Answer:
<h2>The answer is 0.07 mL</h2>
Explanation:
The volume of a substance when given the density and mass can be found by using the formula

From the question
mass = 31 g
density = 444 g/mL
We have

We have the final answer as
<h3>0.07 mL</h3>
Hope this helps you
The final temperature of the mixture : 21.1° C
<h3>Further explanation </h3>
The law of conservation of energy can be applied to heat changes, i.e. the heat received / absorbed is the same as the heat released
Q in(gained) = Q out(lost)
Heat can be calculated using the formula:
Q = mc∆T
Q = heat, J
m = mass, g
c = specific heat, joules / g ° C
∆T = temperature difference, ° C / K
Q ethanol=Q water
mass ethanol=

mass water =

then the heat transfer :

If the grade of the ore is 37.3% nickel, then the unknown quantity to get 10 grams of nickel is 0.373 x = 10 grams or x = 10/0.373=26.8 grams or 0.0268 kg needed to dig up to recover the 10 grams of nickel. At this grade of ore, 1 kilogram would yield 373 grams of nickel.