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2 years ago

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A silver block of silver block of density 10.5 g/cm3 has a volume of 30 cm3. Which of the following is the correct mass of the b

lock

1 answer:

vladimir1956 [14]2 years ago

6 0

<h3><u>Answer</u> :</h3>

➝ Density of block = 10.5 g/cm³

➝ Volume of block = 30 cm³

We have to find mass of block $.$

➠ Density is defined as mass of substance per unit volume $.$

$\dag\:\boxed{\bf{Density=\dfrac{Mass}{Volume}}}$

$:\implies\sf\:Mass=Density\times Volume$

$:\implies\sf\:Mass=10.5\times 30$

$:\implies\boxed{\boxed{\bf{\red{Mass=315\:g}}}}$

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the correct statement is the first

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Explanation:

The law of conservation of energy establishes that the masses are not destroyed, they can only be transformed.

Therefore the mass of carbon in the reactants (CO2 and H2O) must be in the products (glucose and oxygen)

so the correct statement is the first

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2 years ago

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A radioactive isotope has a half-life of 2 hours. If a sample of the element contains 600,000 radioactive nuclei at 12 noon, how

storchak [24]

Answer: There will be 75258 nuclei left at 6 pm.

Explanation:

a) half-life of the radioactive substance:

Half life is the amount of time taken by a radioactive material to decay to half of its original value.

$t_{\frac{1}{2}}=\frac{0.69}{k}$

$k=\frac{0.69}{t_{\frac{1}{2}}}=\frac{0.693}{2hours}=0.346hours^{-1}$

b) Expression for rate law for first order kinetics is given by:

$A=A_0e^{-kt}$

where,

k = rate constant

t = time for decomposition = 6 hours ( from 12 noon to 6 pm)

A = activity at time t = ?

$A_0$ = initial activity = 600, 000

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2 years ago

Imagine you derive the following expression by analyzing the physics of a particular system: M= (mv2r)(mGr2). Simplify the expre

alex41 [277]

Answer:

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Explanation:

From the question we are told that

$M = \frac{ \frac{m v^2}{r} }{\frac{ mG}{r^2 } }$

So simplifying we have

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2 years ago

At 213.1 K a substance has a vapor pressure of 45.77 mmHg. At 243.7 K it has a vapor pressure of 193.1 mm Hg. Calculate its heat

vlabodo [156]

Answer:

$20.3125$ kJ/mol

Explanation:

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2 years ago

A 50.0 kg crate is being pulled along a horizontal, smooth surface. The pulling force is 10.0 N and is directed 20.0 degree abov

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Explanation:

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