Answer:
The reverse of answer B
Explanation:
In a heterogeneous mixture the phases are clearly seen distinguished but a uniform single phase is seen in a homogeneous mixture
The answer is C :
It controls the entry and exit of substances.
<span>Answer: 1.06 moles of molecules = 6.38x10²³ molecules
</span><span />
<span>Explanation:
</span><span />
<span>1) Balanced chemical equation:
</span><span />
<span>2Na + 2H₂O -> 2NaOH + H₂
</span><span />
<span>2) Mole ratios:
</span><span />
<span>2 mol Na : 2 mol H₂O : 2 mol NaOH : 1 mol H₂
</span><span />
<span>3) Convert 48.7 g of sodium to moles:
</span><span />
<span>number of moles = mass in grams / molar mass
</span><span />
<span>molar mass of Na = atomic mass = 23.0 g/mol
</span><span>number of moles = 48.7g / 23.0 g/mol = 2.12 moles of Na</span>
<span /><span>
4) Proportion:
</span><span />
<span>2moles Na/1mol H₂ = 2.12 moles Na / x
</span><span />
<span>x = 2.12 moles Na * 1 mol H₂ / 2 moles Na = 1.06 moles H₂.
</span><span />
<span>5) If you want to convert that to number of molecules you have to multiply by Avogadro's number: 6.022 x 10^²³
</span><span />
<span>1.06 mol x 6.022x10^²³ molecules/mol = 6.38x10²³ molecules</span>
Answer:
NaNO₃
KNO₃
Ca(NO₃)₂
Explanation:
The possible cations for the salt. = Na⁺ , K⁺ , Ca²⁺
The anion for which the formula has to written = NO₃⁻
The salt is of white color.
The possible salts may be:
<u>NaNO₃ </u>
<u>KNO₃</u>
<u>Ca(NO₃)₂</u>
Missy Mae can have one of these salts.
The color of NaNO₃ is from transparent to white.
The color of KNO₃ is white.
The color of NaNO₃ is from white to light grey.
Answer: The object's heat of fusion is 68.52 Joules/gram.
Explanation:
Mass of the sample = 42 grams
Energy required to melt the sample completely = 2878 Joules
The object's heat of fusion is 68.52 Joules/gram.
