Answer:
The given substance is cast iron.
Explanation:
Given data:
Mass of substance = 50 g
Heat absorbed = 23000 J
Initial temperature = 250°C
Final temperature = 1250°C
Which metal is this = ?
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 1250°C - 250°C
ΔT = 1000°C
23000 j = 50 g ×c ×1000 °C
23000 J = 50,000 g. °C×c
c = 23000 J /50,000 g. °C
c = 0.46 J/g.°C
The given substance is cast iron.
The balanced chemical equation will tell you the molar ratios in which hydrogen and oxygen react to form water:
2H2 + O2 ----> 2H2O
Then the ratio is 2 mol of H2 react with 1 mol of O2 and form 2 mol of H2O:
2 : 1 : 2
Now convert the given data into moles:
16 grams of H2 = 16 g / 2 g/mol = 8 mol
16 grams of O2 = 16 g / 16 g/mol = 1 mol.
Then you have that the 1 mol of oxygen will react with 2 moles of hydrogen and they will form 2 mol of H2O.
And you can calculate the mass of 2 moles of H2O by multiplying by its molar weigth: 18 g/mol.
2 mol H2O * 18 g/mol = 36 grams of water.
Then, the answer is 36 grams of H2O.
The activity of the sample is:
R₀ = 4.5 x 10⁻⁶ Ci (3.70 x 10¹⁰ decays/s / 1 Ci)
= 166500 decays / s
The number of nuclei is:
N₀ = (166500 decays/s) / (5730 yr * 3.154 x 10⁷s /1yr) = 9.2 x 10⁻⁷
The mass of a ₆C¹⁴ source is:
m = N₀m₀ = (9.2 x 10⁻⁷) * (2.34 x 10⁻²⁶) = 2.16 x 10⁻³² kg
Answer:
The concentration is 0.036 mg/mL
Explanation:
Concentration = 0.2 mM = 0.2/1000 = 2×10^-4 M = 2×10^-4 mol/L × 180,000 mg/1 mol × 1 L/1000 mL = 0.036 mg/mL
louder sounds
Explanation:
Resonance results in louder sounds.
Resonance is a phenomenon that produces a large vibration as a result of smaller vibration that causes the resonating body to vibrate at its own natural frequency.
Resonance results in sound amplification and causes louder sounds. Increasing vibration results in the production of a louder sound.
Learn more:
Resonance in chemistry brainly.com/question/9422880
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