Answer:
chemical change occur when a substance combines with another to form a new substance.
Explanation:
hope this helps ;)
Compounds are made of two or more atoms of different elements, such as water (H2O) and methane (CH4). Atoms are not drawn to scale. Molecules of compounds have atoms of two or more different elements.
Answer:
I'm guessing that the underlined word is barbarous ... if so the correct answer would be uncivilized.
Explanation:
<span>Answer: 5.32 x 10⁻³ M
Explanation:
1) The rate law for a first order reaction is:
</span><span />
<span>r = - d [A] / dt = k[A]
</span><span />
<span>2) When you integrate you get:
</span><span />
<span> [ A] = Ao x e ^(-kt)
</span><span />
Remember that here A is PH₃
<span>3) Plug in the data: Ao = 0.0316M, k = 0.0180 /s, and t = 99s
</span><span />
<span>[PH₃] = 0.0316 M x e ^( - 0.0180/s x 99s) = 5.32 x 10⁻³ M</span>
The molecular formula of a compound is C₂H₂O₄.
Take 100 grams of compound:
1) ω(C) = 26.7% ÷ 100% = 0.267
m(C) = ω(C) × m(compound)
m(C) = 0.267 × 100 g.
m(C) = 26.7 g.
n(C) = m(C) ÷ M(C).
n(C) = 26.7 g ÷ 12 g/mol.
n(C) = 2.22 mol; amount of carbon
2) ω(H) = 2.2 % ÷ 100% = 0.022
m(H) = 0.022 × 100 g.
m(H) = 2.2 g.
n(H) = 2.2 g ÷ 1 g/mol.
n(H) = 2.2 mol; amount of hydrogen
3) ω(O) = 71.1 % ÷ 100%.
ω(O) = 0.711
m(O) = 0.711 × 100 g
m(O) = 71.1 g
n(O) = 71.1 g ÷ 16 g/mol
n(O) = 4.4 mol; amount of oxygen
4) n(C) : n(H) : n(O) = 2.2 mol : 2.2 mol : 4.4 mol /2.2 mol.
n(C) : n(H) : n(O) = 1 : 1 : 2
M(CHO₂) = 45 amu; empirical formula
90 amu ÷ 45 amu = 2 CHO₂
More info about empirical formula: brainly.com/question/1873039
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