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PSLE Foundation Mathematics

<p>The mass of one atom of nitrogen is $2.33\times {{10}^{-11}}$ picograms. ($1$ pico $={{10}^{-12}}$)</p>
<ol class="i-list"><li><div class="list-item-paragraph">Express this mass in grams, giving your answer in standard form.</div></li><li><div class="list-item-paragraph">A molecule of nitrogen dioxide ${\left(\mathrm{NO}_2\right)}$ contains one atom of nitrogen and two atoms of oxygen.
</div><div class="list-item-paragraph">Given that the mass of one atom of oxygen is $2.66\times {{10}^{-23}}$grams, find the mass of one molecule of nitrogen dioxide.
</div><div class="list-item-paragraph">Give your answer in grams in standard form. </div></li></ol>

The mass of one atom of nitrogen is $2.33\times {{10}^{-11}}$ picograms. ($1$ pico $={{10}^{-12}}$)

Converting Metric Prefixes Using Powers of Ten

Calculations in Standard Form

Standard Form in Atomic Mass Calculations

Standard Form and Compound Interest

<ol class="i-list"><li><div class="list-item-paragraph">The mass of the Sun is $1.99\times {{10}^{27}}$ tonnes.
</div><div class="list-item-paragraph">Write this mass, in kilograms, giving your answer in standard form. ($1$ tonne $=1000$kg)</div></li><li><div class="list-item-paragraph">The radius of a micro-organism is $0.000\,054\,65$cm.
</div><div class="list-item-paragraph">Express $0.000\,054\,65$cm in standard form, giving your answer correct to $3$ significant figures.</div></li></ol>

Standard Form

Significant Figures

Standard Form in Measurement Problems

Approximation and Estimation

<p>The Earth is approximately $150$ gigametres away from the Sun.</p>
<ol class="i-list"><li><div class="list-item-paragraph">Express $150$ gigametres in kilometres, giving your answer in standard form</div></li><li><div class="list-item-paragraph">Light take $3\frac{1}{3}$ nanoseconds to travel $1$ metre. Calculate the time light takes to travel from the Sun to the Earth, giving your answer in seconds, in standard form.</div></li></ol>

The Earth is approximately $150$ gigametres away from the Sun.

Speed, Distance and Time

Standard Form in Astronomy

Ratio, Rate and Speed

<p>The storage capacity of an external hard disk is $3$ terabytes (TB). ($1$ tera $={{10}^{12}}$)<br></p>
<p>If the size of a song clip is $5.5$ megabytes (MB), ($1$ mega $={{10}^{6}}$) how many songs can be stored in the external hard disk?<br></p>
<p>Give your answer in standard form, correct to $3$ significant figures.</p>

The storage capacity of an external hard disk is $3$ terabytes (TB). ($1$ tera $={{10}^{12}}$)


If the size of a song clip is $5.5$ megabytes (MB), ($1$ mega $={{10}^{6}}$) how many songs can be stored in the external hard disk?


Give your answer in standard form, correct to $3$ significant figures.

Standard Form and Data Storage

<p>A particle has a mass of $273$ picograms. ($1$ pico $={{10}^{-12}}$)</p>
<ol class="i-list"><li><div class="list-item-paragraph">Express this mass in grams.<br></div><div class="list-item-paragraph">Give your answer in standard form.</div></li></ol>
<p>A small bottle contains $0.3$ billion of such particles. ($1$ billion $={{10}^{9}}$)</p>
<ol class="i-list" start="2"><li><div class="list-item-paragraph">Find the total mass of the particles in the bottle.<br></div><div class="list-item-paragraph">Give your answer in grams as a normal decimal number.</div></li></ol>

A particle has a mass of $273$ picograms. ($1$ pico $={{10}^{-12}}$)

A small bottle contains $0.3$ billion of such particles. ($1$ billion $={{10}^{9}}$)

Using Standard Form with Metric Prefixes

<p>The diameter of a circular animal cell is $23.7$ micrometres.   ($1$ micro =$10^{-6}$)</p>
<ol class="i-list"><li><div class="list-item-paragraph">Express $23.7$ micrometres in metres, giving your answer in standard form.  </div></li><li><div class="list-item-paragraph">Find the circumference of the circular animal cell in metres, giving your answer in the standard form.</div></li></ol>

The diameter of a circular animal cell is $23.7$ micrometres.   ($1$ micro =$10^{-6}$)

Circumference and Area of Circles

Standard Form in Biological Measurements

Perimeter and Area of Plane Figures

<p>$1.38\times {{10}^{-6}}$ seconds can be written as&nbsp;$k$ nanoseconds.  (1 nano = ${{10}^{-9}}$)<br>Find $k$.</p>

$1.38\times {{10}^{-6}}$ seconds can be written as $k$ nanoseconds.  (1 nano = ${{10}^{-9}}$)
Find $k$.

Standard Form and Unit Conversion

<p>The Earth is approximately $0.787$ terametres (Tm) (1 tera $=\mathrm{ }{{10}^{12}}$) away from the Jupiter.<br>Light takes about $8.936$ nanoseconds (1 nano $=\mathrm{ }{{10}^{-9}}$) to travel $3$ metres.<br>Leaving your answers in standard form,</p>
<ol class="i-list"><li><div class="list-item-paragraph">express $0.787$ Tm in m.</div></li><li><div class="list-item-paragraph">calculate the time taken, in seconds, for light to travel from the Earth to Jupiter.</div></li></ol>

The Earth is approximately $0.787$ terametres (Tm) (1 tera $=\mathrm{ }{{10}^{12}}$) away from the Jupiter.
Light takes about $8.936$ nanoseconds (1 nano $=\mathrm{ }{{10}^{-9}}$) to travel $3$ metres.
Leaving your answers in standard form,

Common Prefixes in our Daily Life

<p>The diameter of a circular organism is $7$ micrometres. ($1$ micro $={{10}^{-6}}$)</p>
<ol class="i-list"><li><div class="list-item-paragraph">Express $7$ micrometres in metres.</div></li><li><div class="list-item-paragraph">Find the area, in square metres, of the circular organism, giving your answer in standard form.</div></li></ol>

The diameter of a circular organism is $7$ micrometres. ($1$ micro $={{10}^{-6}}$)

<p>The atomic radius of hydrogen is about $53$ picometres.   ($1$ pico $={{10}^{-12}}$)</p>
<p>Express $53$ picometres in metres, giving your answer in standard form.</p>

The atomic radius of hydrogen is about $53$ picometres.   ($1$ pico $={{10}^{-12}}$)

Express $53$ picometres in metres, giving your answer in standard form.

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