European Baccalaureate essentials: original practice

Original practice on European Baccalaureate scoring, Mendelian ratios, and pH, plus a short quiz.

3 flashcards · Curadoria: Ada

Pergunta 1: What overall percentage is needed to pass the European Baccalaureate, and how is the final mark reported?

Resposta

60 out of 100. The final result is a percentage from 0 to 100.

The European Baccalaureate reports a final percentage from 0 to 100. A candidate passes at 60, and participating countries recognize the result for university admission.

Pergunta 2: Two heterozygous parents (Aa x Aa) are crossed. What fraction of the offspring is expected to show the recessive trait?

Resposta

One quarter, or 25%.

The cross gives AA, Aa, Aa, and aa. Only aa shows the recessive trait, so 1/4 of the offspring are expected to show it.

Pergunta 3: What is the pH of a 0.010 M solution of HCl, a strong acid?

Resposta

pH 2.0.

HCl dissociates completely, so the hydrogen ion concentration is 0.010 M, or 10^-2 M. The pH is the negative log of that value, which is 2.0.