Answer:
3.46x10⁴
Explanation:
Hello,
In this case, we can see that the number 34,560 has five significant figures, it means that if we want to write it with three, we must take the 3, 4 and 5 only. Nevertheless, since the 6 after the five is greater than 5, we can round such five to 6, so we obtain:
346
However, the decimal places cannot get lost, therefore, we move the given thousand to the three, so the number turns out:
3.46x10⁴
Best regards.
<span>6.38x10^-2 moles
First, let's determine how many moles of gas particles are in the two-liter container. The molar volume for 1 mole at 25C and 1 atmosphere is 24.465 liters/mole. So
2 L / 24.465 L/mol = 0.081749438 mol
Now air doesn't just consist of nitrogen. It also has oxygen, carbon dioxide, argon, water vapor, etc. and the total number of moles includes all of those other gasses. So let's multiply by the percentage of nitrogen in the atmosphere which is 78%
0.081749438 mol * 0.78 = 0.063764562 mol.
Rounding to 3 significant figures gives 6.38x10^-2 moles</span>
Answer:
L/EGFOU;T4444444444444444444444czgfryewi;adkb,SJJ>RL:IAO:YHSBRAGldOUSDHRIUITUER
Explanation:
DHFUIEY7RY8EFUIDJKJEUSDYRIFU8ERJFHJSX
Answer:
0.75 cal/g°c
Explanation:
for specific heat we have formula:
Amount of heat absorbed or released = mass x specific heat of a substance x change in temperature.
ΔQ=m x c x ΔT
where c= specific heat
m= mass of a substance
ΔT = total temperature
ΔQ = Amount of heat
so for specific heat,
c= ΔQ/mxΔT
c= 280/25x (25-10)
c= 280/375
c= 0.75 cal/g°c
Answer:
0.175mol
Explanation:
Mole of a substance can be calculated using the formula as follows:
number of moles (n) = mass (m) ÷ molar mass (MM)
According to this question, there are 4.2g of Magnesium (Mg).
Molar mass of Magnesium = 24g/mol, hence, the number of moles of 4.2g of Mg is as follows:
n = 4.2g ÷ 24g/mol
n = 0.175mol
